SOLAR-THERMAL POWERED AIRCONDITIONER FOR … · SOLAR-THERMAL POWERED AIRCONDITIONER FOR ELECTRIC...

EML 4905 Senior Design Project

A B.S. THESIS

PREPARED IN PARTIAL FULFILLMENT OF THE

REQUIREMENT FOR THE DEGREE OF

BACHELOR OF SCIENCE

IN

MECHANICAL ENGINEERING

SOLAR-THERMAL POWERED

AIRCONDITIONER FOR ELECTRIC

TROLLEY

Final Report

Adrian F. Gonzalez

Daniel Pico

Advisor: Professor Andres Tremante

November 23, 2016

This B.S. thesis is written in partial fulfillment of the requirements in EML 4905.

The contents represent the opinion of the authors and not the Department of

Mechanical and Materials Engineering.

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Ethics Statement and Signatures

The work submitted in this B.S. thesis is solely prepared by a team consisting of Adrian Gonzalez

and Daniel Pico and it is original. Excerpts from others’ work have been clearly identified, their

work acknowledged within the text and listed in the list of references. All of the engineering

drawings, computer programs, formulations, design work, prototype development and testing

reported in this document are also original and prepared by the same team of students.

Signature1

Adrian F. Gonzalez

Team Leader

Daniel Pico

Team Member

Advisor Signature

Dr. Andres Tremante

Faculty Advisor

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Contents Ethics Statement and Signatures ............................................................................................................... ii

Abstract ........................................................................................................................................................ 2

1. Introduction ..................................................................................................................................... 3

1.1 Problem Statement ........................................................................................................................ 3

1.2 Motivation ..................................................................................................................................... 6

1.3 Literature Survey .......................................................................................................................... 6

1.4 Survey of Related Standards ......................................................................................................... 9

1.5 Discussion ................................................................................................................................... 10

2. Project Formulation ...................................................................................................................... 11

2.1 Overview ..................................................................................................................................... 11

2.2 Project Objectives ....................................................................................................................... 11

2.3 Design Specifications .................................................................................................................. 12

2.4 Addressing Global Design .......................................................................................................... 13

2.5 Constraints and Other Considerations ......................................................................................... 13

2.6 Discussion ................................................................................................................................... 14

3. Design Alternatives ....................................................................................................................... 15

3.1 Overview of Conceptual Designs Developed ............................................................................. 15

3.2 Design Alternate 1 ...................................................................................................................... 15



3.5 Integration of Global Design Elements ....................................................................................... 17

3.6 Feasibility Assessment ................................................................................................................ 18

3.7 Proposed Design ......................................................................................................................... 18

3.8 Discussion ................................................................................................................................... 19

3.9 Discussion ................................................................................................................................... 19

4. Project Management ..................................................................................................................... 20

4.1 Overview ..................................................................................................................................... 20

4.2 Breakdown of Work into Specific Tasks .................................................................................... 20

4.3 Gantt Chart for the Organization of Work and Timeline ............................................................ 24

(Timeline for Senior Design Organization and Senior Design time frame) ........................................... 24

4.4 Breakdown of Responsibilities Among Team Members ............................................................ 26

(Indicate Each Member’s Major and Support Roles for Each Task) ...................................................... 26

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4.5 Patent/Copyright Application ..................................................................................................... 26

4.6 Commercialization of the Final Product ..................................................................................... 27

4.7 Discussion ................................................................................................................................... 27

5. Engineering Design and Analysis ................................................................................................ 27

5.1 Overview ..................................................................................................................................... 27

5.2 Kinematic Analysis and Animation ............................................................................................ 32

5.2.1 Sub-Project Objectives ............................................................................................................ 32

5.2.2 Design Specifications .............................................................................................................. 33

5.2.3 Base Frame .............................................................................................................................. 33

5.2.4 Front Frame ............................................................................................................................. 34

5.2.5 Back Frame ............................................................................................................................. 34

5.3 Dynamic/Vibration Analysis of the System ................................................................................ 35

5.4 Structural Design ........................................................................................................................ 36

5.4.1 The Base .................................................................................................................................. 36

5.4.2 The Front Frame...................................................................................................................... 38

5.4.3 The Back Frame ...................................................................................................................... 41

5.5 Material Selection ....................................................................................................................... 44

5.5.1 Structural Steel Selection ........................................................................................................ 44

5.5.2 Hardware and Damping Components ..................................................................................... 46

5.6 Component Design/Selection ...................................................................................................... 49

5.6.1 Piping Network Design ........................................................................................................... 51

5.6.2 Solar Collector Design ............................................................................................................ 54

5.6.2.1 Different types of Solar Collectors ......................................................................................... 54

5.6.2.2 Design Specifications .............................................................................................................. 57

5.6.2.3 Design Considerations ............................................................................................................ 57

6. Prototype Construction ................................................................................................................ 64

6.1 Overview ..................................................................................................................................... 64

6.2 Description of Prototype ............................................................................................................. 64

6.3 Prototype Design ......................................................................................................................... 64

6.4 Parts List ..................................................................................................................................... 65

6.5 Construction ................................................................................................................................ 66

6.6 Prototype Cost Analysis .............................................................................................................. 66

6.7 Discussion ................................................................................................................................... 67

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7. Design Considerations .................................................................................................................. 67

7.1 Health and Safety ........................................................................................................................ 67

7.2 Assembly and Disassembly ........................................................................................................ 68

7.3 Manufacturability ........................................................................................................................ 68

7.4 Maintenance of the System ......................................................................................................... 69

7.4.1.1 Maintenance of Chiller ............................................................................................................ 69

7.4.1.2 Maintenance of Fan Coil ......................................................................................................... 70

7.5 Environmental Impact and Sustainability ................................................................................... 71

7.6 Economic Impact ........................................................................................................................ 72

7.7 Risk Assessment ......................................................................................................................... 72

8. Design Experience ......................................................................................................................... 72

8.1 Overview ..................................................................................................................................... 73

8.2 Standards Used in the Project ..................................................................................................... 73

8.2.1 ANSI/ASHRAE Standard 15: Safety Standard for Refrigeration Systems ............................ 74

8.2.3 ANSI/IIAR 2-2008: American National Standard for Equipment, Design, and ..................... 74

8.2.5 ASME B31.8 Gas Transportation and Distribution Piping System ........................................ 74

8.2.6 ASME B31.5 Refrigeration Piping ......................................................................................... 75

8.3 Contemporary Issues ................................................................................................................... 75

8.4 Impact of Design in a Global and Societal Context .................................................................... 75

8.5 Professional and Ethical Responsibility ...................................................................................... 76

8.6 Life-Long Learning Experience .................................................................................................. 76

9. Conclusion ..................................................................................................................................... 76

9.1 Conclusion and Discussion ......................................................................................................... 76

9.2 Evaluation of Integrated Global Design Aspects ........................................................................ 78

9.3 Evaluation of Intangible Experiences ......................................................................................... 78

9.4 Commercialization Prospects of the Product .............................................................................. 79

9.5 Future Work ................................................................................................................................ 79

10. References ...................................................................................................................................... 80

10.1 Literary References ..................................................................................................................... 80

References .................................................................................................................................................. 80

10.2 Index of Figures .......................................................................................................................... 81

10.3 Index of Tables ........................................................................................................................... 83

11. Appendices ..................................................................................................................................... 83

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A. Detailed Engineering Drawings of All Parts, Subsystems and Assemblies .................................... 83

B. Multilingual User’s Manuals .......................................................................................................... 83

C. Excerpts of Guidelines Used in the Project .................................................................................... 83

(Standards, Codes, Specifications and Technical Regulations; Quotes with references, or scanned

material as appropriate) ........................................................................................................................... 83

D. Copies of Used Commercial Machine Element Catalogs (Scanned Material) ............................... 84

E. Detailed Raw Design Calculations and Analysis (Scanned Material) ............................................ 87

12. Project Photo Album .................................................................................................................... 96

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Abstract

As the climate continues to change due to human expansion of the “greenhouse effect”

and the reserves of nonrenewable resources keep decreasing, the use of alternative forms

of energy becomes imperative for a sustainable future. Today, more than ever, there is a

growing concern about the environmental pollution caused by burning fossil fuels and an

awareness of the need of developing new technologies capable of exploiting renewable

sources of energy that can meet the world growing demands at competitive prices. To

mitigate these environmental concerns, the transportation system in the United States is

increasingly promoting the use of battery-powered buses to diminish the emission of

carbon dioxide to the atmosphere and, thus, improve the air quality. One solution to this

problem is the implementation of battery- powered electric buses. The problem with this

solution is that electric vehicles have a very limited driving range. Compared to an

electric car, the mass of a bus is much larger so the effective range is much lower (it can

be as little as 30 miles). Moreover, in an electric vehicle with no internal combustion

engine to drive the A/C compressor, the air-conditioning has to be run electrically just

like a residential air-conditioning system. This represents a challenge since running a bus

A/C requires several kilowatts of power and taking it from the battery will drastically

reduce the driving range. The city of Sweetwater wants to address this problem by using

an air-conditioning system powered by solar energy. Therefore, our challenge is to find

and implement a solution that is both efficient, cost-effective, and environmentally

friendly. This challenge will be carried out by two teams. One team will design a solar

water heat panel which will be used by our team to provide the required heat necessary to

power the chosen absorption chiller.

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This project represents the combination of several technologies to create a vehicle which

uses little-to-no fossil fuels. Increasingly important is the implementation of renewable

energy with the purpose of reducing the pollution of the city. Public transportation is an

important part of life in a large city. This project combines an Absorption Chiller with a

Solar Collector so that the climate control apparatus does not pull power from the

propulsion system of the vehicle. This will raise the efficiency of the vehicle and

eliminate the use of synthetic refrigerants. Furthermore, once the climate control

apparatus is finalized, the technology used may be applied to the design of an alternative-

energy propulsion system. This report focuses on the first phase of the project: the retrofit

of an existing absorption chiller to the trolley.

1. Introduction

1.1 Problem Statement

Most vehicles on the road today have air conditioning provided to the user/occupant. Most,

if not all, of these vehicles utilize a compressor to drive the air conditioning system using

the Carnot Cycle. While these systems boast relatively high efficiency (when compared to

the Absorption Cycle-based counterparts), the design of such systems does not allow for

the direct use of renewable energy. Implementing a form of renewable energy offers the

possibility of capturing an abundant energy source that replenishes itself continuously

without affecting the Earth’s resources (U.S. Department of Energy, 2016). The sun is the

largest source of energy known to our planet. As such, a solar heat powered absorption

chiller can provide cooling to any scenario. In this case, it will provide air conditioning to

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an electric Trolley. The design will consist of an absorber, a generator, a hot water pump,

a chilled water pump, and a water heating device located on the roof of the trolley. These

items come together to provide cooling comfort to the residents of Sweetwater while still

protecting the environment. The system will be composed of three main phases in the

energy generation cycle. These are the evaporation, absorption, and power cycles. First,

the liquid refrigerant selected will evaporate under low pressure in order to extract heat

from its surroundings. Second, during the absorption process, the liquid substance is

absorbed by another substance allowing more refrigerant to be processed. Third, the

mixture is heated thereby increasing its partial pressure without affecting the overall

pressure of the system. Finally, the refrigerant is condensed through the heating device to

continue supplying the evaporator with refrigerant in order to cool (ROBUR, 2016).

The design and construction of a vehicle which is powered by renewable energy is a

complex challenge because of the myriad of requirements which constitute a “practical”

design. Most of these requirements are founded on the expectations of the end user. Such

requirements include but are not limited to:

1) Reasonable, Operational Range

2) Amenities within:

a. Air Conditioning

b. Support for Electronic Devices (ex; power outlets, wifi, etc.)

c. Comfortable Seating

d. Accessibility

3) Performance

a. Power

b. Acceleration

c. Stability

d. Smooth Response

e. Precise Control

f. Low Noise

g. Mechanical Efficiency

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Apart from the demands of the end user are the requirements for creating a vehicle

which utilizes alternative energy. The concept of an alternative energy vehicle is an

ideal model. The features of such a model include the following additional

requirements:

1) Minimal production of Chemical Waste and Pollutants

2) Power Efficiency

3) The utilization of an Alternative Energy Source

4) The supplemental use of Electrical/Thermal Energy to eliminate the reliance

on Fossil Fuels

Superseding both of the previously mentioned sets of requirements are the demands for

safety and reliability. Many alternative energy devices in existence today utilize rare earth

resources or utilize chemicals which require special handling and safety measures. The

reactiveness of the chemicals used and the relative stability of the environment in which

they will be used, are important factors that can either foster or hamper the feasibility of a

design.

In this project, we face the challenge of designing a practical, environmentally-friendly,

and efficient air conditioning system to power a fully electrical trolley. The reason for an

external source of energy to power this trolley is that using its own battery will result on a

more limited driving range which will be very inconvenient. The required external source

of energy is solar heat since it is free, renewable, and easy to harvest. A team will be

designing and implementing a solar water heat panel which will be used by our team to

provide the required heat necessary to power our system which consists of a 5-ton gas fired

absorption chiller by Robur Industries.

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1.2 Motivation

This project will be used to prove/disprove whether or not solar/thermal energy can be

used to power one of several peripheral systems present on most vehicles. If the project

is successful, the research and testing can be used as the basis for further development

of the overall concept and other projects as well.

The purpose of this project is to create a vehicle which requires less energy to operate

and to further the concept in the future by making the entire vehicle run on alternative

energy. The motivation for these parameters are as follows:

1) To create a vehicle which provides air conditioning to its passengers by use of

alternative energy. This will allow the vehicle to use less fuel even if the propulsion

system is driven by fossil fuels.

2) To modify an absorptive chiller unit so that the generator component is driven by

hot water instead of the burning of gas. This is an important modification which will

minimize the dependency of the vehicle on combustible fuels.

3) To enable the selection and design of a suitable, alternative energy, propulsion

system. Once the A/C system is perfected, the overall vehicle may be analyzed and a

suitable alternative energy power system may be selected and designed.

1.3 Literature Survey

There are many forms of alternative energy available to the world today. These sources

include solar, wind, hydro-electric, plant-based fuels, hydrogen, nuclear, etc. In recent

years, there has been a push to promote electric vehicle propulsion. Manufacturers,

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such as Ford, General Motors, and Tesla, have all made battery electric vehicles

commercially available. The reduction in pollution and the long-term cost savings

obtained by not using pricey fossil fuels, has motivated consumers and businesses to

rethink their personal and work vehicles. This is not to say that that fossil fuels are not

being used to charge the batteries, but there is energy spent in the refinement of fossil

fuels as well.

Most power plants use Hydro-Carbon fossil fuels, while others use radioactive

materials to generate electricity to send to homes and businesses (U.S. Department of

Energy, 2016). Although these centrally placed power-plants are the main supplier of

energy, there has been an increase in the variety of products which are commercially

available to convert the building/home into a “Green” structure, relying on little or no

fossil-fuels/grid electricity. They only need to be further developed and implemented

and society will benefit from this.

In addition to the power consumption of buildings and homes, personal and commercial

vehicles add greatly to the amount of carbon in our atmosphere. Most vehicles run on

gasoline or diesel-gasoline fuel. Nearly all vehicles utilize an air conditioning system

which is powered by the rotations of the motor. In this layout, which is typical of most

vehicles, the power is used in a “parasitic” mode where the Compressor of the A/C

system is using power that would otherwise be sent to the drivetrain of the vehicle. This

extra demand placed on the motor results in more fuel burned to travel the same

distance. In all air conditioning systems which utilize the Carnot Cycle, a compressor

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does the job of pushing the coolant through the plumbing and expansion/compression

valves. In this project, the air conditioning system will utilize an Absorption Chiller.

Like the compressor in an electric vapor pressure cycle, the absorption system utilizes

its thermal compressor, which consists of the generator, absorber, pump and heat

exchanger, to boil the water vapor out of a solution and compress the refrigerant vapor

to a higher pressure. Increasing the refrigerant pressure likewise increases its

condensing temperature (ROBUR, 2016). The refrigerant vapor condenses to a fluid at

this higher pressure and temperature. Since this condensing temperature is hotter than

the surrounding temperature, heat moves from the condenser to the ambient air and is

rejected. The high-pressure fluid then goes through a throttling valve that decreases its

pressure. Decreasing its pressure likewise diminishes its boiling point temperature. The

low-weight fluid then goes into the evaporator and is boiled at this lower temperature

and pressure. Since the boiling temperature at this time is lower than the temperature

of the conditioned air, heat moves from the conditioned air stream into the evaporator

and causes this fluid to boil. Expelling heat from the air in this way causes the air to be

cooled. The refrigerant vapor then goes into the absorber where it comes back to a

liquid state as it is pulled into the lithium bromide solution (the absorption process).

The diluted lithium bromide solution is pumped back to the generator. Since lithium

bromide (the absorbent) does not boil, water (the refrigerant) is effortlessly isolated by

adding heat. The resultant water vapor goes into the condenser, the absorbent solution

comes back to the absorber, and the same procedure start again.

By using the Absorption Chiller, the power demand is removed from the Propulsion

System of the vehicle, which raises the efficiency of its operation. The stand-alone air

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conditioning system can then be powered by other means, electricity or renewable

energy. In the case of this project, the Absorption Chiller uses Liquid Propane Gas or

Natural Gas to heat the Generator Vessel. Although this system is still using fossil-

fuels, these two types supply reasonable power while releasing a smaller quantity of

harmful pollutants. According to the U.S. Energy Information Administration, Coal

(typically used to generate electricity in steam power plants) produces almost 2 times

(1.95) the amount of CO2 that Natural Gas (NG) does, and 1.64 times that of Liquid

Propane Gas (LPG). More relevant to this project, Gasoline produces roughly 13%

more CO2 than LPG while Diesel-based fuels produce 16% more (U.S. Department of

Energy, 2016).

1.4 Survey of Related Standards

Standards are documents that are established by consensus and approved by a recognized

entity to ensure the reliability of documents, products, and services people use every day.

Standards are developed to support and facilitate the implementation of integrated

solutions. They reduce unnecessary variety in the marketplace and simplify product

development. They also enable economies of scale which result in a reduction in the cost

of producing a product. Standards also offer many benefits such as safety and reliability

as well as interconnection and interoperability.

SAE J2683_201603, Refrigerant Purity and Container Requirement for Carbon Dioxide

Used in Mobile Air-Conditioning Systems

ASME B31.8 Gas Transportation and Distribution Piping Systems

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ASME B31.5 Refrigeration Piping

1.5 Discussion

As was previously mentioned, LPG and NG fuels release 13-16% less the amount of

pollutants that the combustion of Gasoline or Diesel fuel does. Although this is a

relatively small energy savings, the true value of the Absorption Chiller comes from the

potential modifications which can be made. In the case of this design, the Generator

Vessel is heated to the requisite 305° by means of another thermal source; a closed, “Hot

Water” loop. By changing the source to a heated liquid, several input-sources may be

used to heat the same medium. This design uses a combination of sources; a Solar

Collector, a Hot Exhaust Gas Scavenger and an auxiliary LPG/NG Burner. The burner

still provides a means of heating the system completely, but the other two sources reduce

the consumption of the Burner. The reduction of fuel consumption has two main

advantages, and yet a third which is implicitly related to the second. The first benefit is

the reduction of harmful pollutants which will, inevitably be released into the

atmosphere. The second advantage is the lowering of the operational costs, due to a

reduction in consumption. The third advantage is the possibility of return on investment.

If the Exhaust Thermal Scavenger and Solar Collector are efficient and effective enough,

the amount of money saved can help reimburse a portion of the initial investment and

may even generate an income after the break-even point.

In order for this concept to work, a Heat Exchanger must be used to interface the

Generator Vessel with the heated fluid. Based on design histories, we know that the

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optimal design for the heat exchange of two fluids, where conduction is the main mode of

heat transfer, is the Tube-In-Tube Exchanger

2. Project Formulation

2.1 Overview

This project is an ongoing effort to develop an air conditioning system for the FIU

battery-powered electric trolley. An external source of energy ought to be used so that the

driving range of the trolley is not affected by the power required to run the A/C. Taking

advantage of free, renewable solar energy, a second team will design a solar water

heating panel which will be used by our team to power an absorption chiller. The chiller

will be chosen, redesigned and modified to fit in the available space, work with the solar

heating panel, and comply with the corresponding standards.

2.2 Project Objectives

The main objective of this project is to successfully design and build the necessary

modifications required to allow a commercially available absorption chiller to function as

the air conditioning unit for the FIU battery-electric trolley. The modifications include

converting a direct-fired absorption chiller into one that utilizes hot water as its main

source of energy. The main design component is the hot water heat exchanger that is to

interact with the generator of the chiller.

Another objective of the project is to physically install the absorption chiller system

within the trolley. This includes the hot water loop between the solar heat collector and

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the hot water heat exchanger at the generator, the fan coil installed within the passenger

cabin, and the chilled water loop between the chiller and the fan coil. This also includes

modification to the trolley to allow for proper ventilation of the chiller’s condenser

section.

Of course, our objectives also include collaboration. The overall intention is for the

absorption chiller to provide the necessary cooling to the trolley without reducing its

driving range since it will not run on electric power. A key component to this project is

to successfully integrate a solar water heating panel which was designed by another team

with our selected absorption chiller. This requires close collaboration between both

teams to ensure that their solar panel can provide the necessary heat to our chiller.

2.3 Design Specifications

In order to successfully design the A/C system, several factors have been taken into

consideration. The absorption chiller being utilized is a 5 ton unit manufactured by

Robur Industries. It is essentially a single-phase absorption chiller. The cooling system

is arranged with four components. These are the generator, the condenser, the

evaporator, and the absorber. Since the chiller works through the conversion of energy, it

is imperative that the chiller be exposed to a source of heat capable of providing an

adequate amount of heat as required to operate at maximum capacity. The hot water loop

must carry this heated water from the solar water heating panel to the new hot water heat

exchanger. This heat exchanger must be cable of containing the high-pressure, hot water

that will be circulating at the base of the generator so that the reaction can occur within

the system. If the heat exchanger fails to provide and/or contain enough heat at the

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generator, the cooling cycle will fail to generate enough chilled water to cool the air

passing through the fan coil within the trolley.

2.4 Addressing Global Design

There are various advantages to using a Solar Heat Powered Air Conditioner. One

advantage is the opportunity to replace the current cooling system with an alternative

energy based one while simultaneously reducing operating costs due to cooling. This

includes reducing electrical consumption because the chiller will depend greatly on freely

collected solar heat and minimally on external provided electrical power used to run the

fan and pump motors. Further, since the main energy source for the chiller is actually a

renewable energy source such as solar heated water, the system becomes quite near

carbon neutral.

Since the system relies on the free energy from the sun, it works best in climates where

abundant solar heat is available and consistent. Therefore, worldwide applications are

not ideal. However, there are numerous geographical regions throughout the world that

could benefit from this system. As such, the user manual would be available in different

languages including English, Spanish, Italian, Greek, French, Arabic, etc. Programs such

as Google TranslateⓇ can help with this endeavor. These manuals will include

installation instructions, maintenance, replacement parts, etc. The user manual should

include both SI and Imperial units of measure depending on the geographical location.

2.5 Constraints and Other Considerations

There are various constraints associated with this project. On the one hand, our design

depends on the ability of a second team to design a solar water heating panel that is able

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to provide the required heat to our absorption chiller. They, in turn, have their own

constraints such as dependency on the sunlight being present long enough to provide

sufficient energy to the solar panel. This turned out to be a choke point in the project as a

full-size solar water heating panel was not built in order for us to test our system.

Therefore, we were only able to run simulations to test our design.

Space was another issue to consider in this design. The initial idea was to disassemble the

chiller including separating the condenser coil from the rest of the chiller. This would

allow us to install the condenser coil at the front of the trolley like a radiator and the

remainder of the components at the rear in a relatively small compartment. However, this

would have required the handling of toxic chemicals such as ammonia. A final decision

was made to install the chiller as one piece in the free space at the back of the trolley.

Since there is no passenger seating in this area, it was considered best to partition it off

and make it mechanical room of sorts.

2.6 Discussion

Overall, the design of the Solar Heat Powered Air Conditioner for the Electric Trolley

provides numerous advantages over conventional systems. Similarly, there are numerous

hurdles to overcome and restrictions to use of the final product. In all, once all the

factors have been considered, the design is fundamentally sound and proposes to advance

the discussion for utilization of renewable resources paired with existing technologies.

The design shows that new efficiencies can still be exploited within existing fields of

study.

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3. Design Alternatives

3.1 Overview of Conceptual Designs Developed

A number of different concepts were developed during the design phase of this project.

These concepts included alternate sources of heat, alternate refrigerants, alternate

physical layouts, and others. Each option was thoroughly discussed for pros and cons as

well as vetted for inclusion in this design or suggested for future iterations of the project.

3.2 Design Alternate 1

The first design alternative considered was to convert the chiller to use Lithium Bromide

as the refrigerant in lieu of the Ammonia. This alternative makes the system more

environmentally friendly once in mass production. Any unwanted leaks due to system

failure or physical damage would not expose the user to the toxicity of the Ammonia.

Unfortunately, this conversion proved to be too expensive. The only commercially

available chiller that was attainable within the budget was designed to use Ammonia. As

it is, the chiller used up most of the resources that were available including a grant as well

as a private donation by a local company. Further, draining the Ammonia from the

system could prove to be dangerous to the team as the team is not properly trained to

handle toxic chemicals. Lastly, despite the drawbacks, Ammonia is actually quite

accessible throughout the world. Fortunately, this adds to the Global Design aspect.

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The second design alternative was to include a Hybrid Hot Water / Gas Fired option. The

premise behind this option is to overcome situation when the solar water heater fails to

provide enough heat or a high enough temperature to allow the absorption process to

occur within the chiller. The Gas Fired portion of this option would provide an in-line

gas-fired water heater, installed on the section of pipe running from the solar water heater

to the generator inlet. If the temperature is not ideal, the controller would activate the

secondary heating stage to boost the temperature of the incoming water to ensure the

reaction occurs. This option would greatly increase the usable reach of the design as it

would no longer be limited to areas that have consistent solar heat available. However,

this option would rely on a removable or refillable natural gas or propane tank to fuel the

gas water heater. Note, the system will still benefit from the solar water heater, but it

would also be able to function when the solar water heater falls short of the design

performance. However, this option could prove to be quite cumbersome in application.

Constant replacing or refilling of the tank is not ideal. The principle is sound, but the

execution still needed more work.


The third design alternative is to include a battery and drive motor heat recovery option.

Depending on the design, one major design constraint for electric drive systems is heat

generated by the batteries and drive motor. Some electric cars use ambient air to cool the

batteries, but as they heat up, the efficiency drops. Some cars use the on-board air

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conditioner to cool the batteries, but this is a double-edged sword as the air conditioner

drains the batteries while in use. The third design alternative would include a heat

recovery system run between the battery banks as well as around the drive motor. This

would help to keep the components of the electric drive system operating at ideal

temperatures and efficiencies while also providing additional heat to run the chiller. This

design would further increase the effective efficiency of the system as it incorporates an

additional free heat source. However, as the electric drivetrain has not been designed,

this option was not available for incorporation into the project.

3.5 Integration of Global Design Elements

The fourth design alternative was considered by the team to be the ideal design. This

design is for incorporating the absorption chiller into a Plug-In Hybrid trolley. The

trolley would have a battery-powered electric drivetrain as well as an on-board natural-

gas fueled generator to charge the batteries should the need arise. This option extends the

usable range of the trolley. As for the chiller, the system would utilize the solar water

heater as well as a heat recovery system for the internal combustion engine and the gas-

fired heat exchanger from Design Alternative 2. Fortunately, in lieu of the separate tank,

the system could utilize the same natural gas tank that fuels the generator. Unfortunately,

as before, the drivetrain for the trolley is not yet finalized. Therefore, this design

alternative must be shelved for future iterations.

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3.6 Feasibility Assessment

The final design incorporates the use of freely available solar heat as its main energy

source. Further, the refrigerant, despite its drawbacks, is readily available worldwide.

The core of the system is extremely adaptable to many applications, and the technology

behind the design is very well established. The concept of using existing technology and

combining it with readily available renewable energy has immeasurable global reach.

The key to the success of this design is to present it to the various markets showing how

it can be adapted. This includes presenting the designs, manuals, etc. in various

languages.

3.7 Proposed Design

The final is design should be quite feasible. The major components, such as the chiller,

fan coil, pumps, etc., are readily available in the market, and the funds were acquired to

push the project forward. However, as previously mentioned, it does depend on the

success of other teams. In order to test the final design, it is imperative that a full-scale

solar water heater be constructed and incorporated into the trolley. Further, proper power

for the pump and fan motors would depend on finalizing the battery bank for the electric

trolley.

19

3.8 Discussion

The proposed design is modify the gas-fired absorption chiller to function on hot water

that is to be supplied by a roof-mounted solar water heating panel as designed by other.

The design includes a new hot water heat exchanger to encase the generator portion of

the absorption chiller. The chiller is to be installed in the rear section of the trolley where

there is no passenger compartment. The rear space is to be partitioned off from the

passenger space. The rear section is to become a mechanical plenum for the condenser

section of the chiller including louvers for intake and exhaust. A chilled-water fan coil is

to installed within the passenger area. This fan coil is to piped to the chiller so that it can

provide cold air the passenger area.

3.9 Discussion

Despite many superior alternate designs that could not be implemented, the fundamental

basics of the design provide an excellent basis from which to build for future iterations.

The design show proof of concept for the integration of existing technologies with

renewable resources to find new efficiencies. Also, despite the costly components

required, the design prototype shows excellent promise and continues to draw interest

from various organizations and local markets.

20

4. Project Management

4.1 Overview

From the outset of this project, it was understood that completion would require the

integration of previous research with the current research and related system components.

The previous research on solar collectors was supposed to be harnessed so that a working

prototype collector could be built and tested, with the intention of integrating it to the

Absorption Chiller for a full prototype. After reviewing the previous research, it was

determined that the data collected was unsatisfactory and the prototype would not be

efficient enough to be considered for the demands of the Absorption Chiller. As such,

further research would need to be conducted on solar collectors. Another crucial aspect of

this system, which was originally underestimated, is the design and implementation of a

heat exchanger which could receive the thermal transport medium (liquid; water,

ammonia, lithium bromide) and adequately transfer the necessary thermal power, at the

requisite temperature. This aspect of the project took more time and effort in formulation

and simulation, than was previously expected.

4.2 Breakdown of Work into Specific Tasks

After performing preliminary research and gaining an awareness of the sub-tasks

associated to each facet of this project, it has become clear that the overall project

requires further compartmentalization and development. Each facet could be its own

project. Below is a breakdown of specific sub-tasks and the major components of the

project to which it contributes;

21

Modification of Robur Absorption Chiller

Extraction/Purging of existing Ammonia-Water solution from Primary

loop of Chiller

Removal of LPG/NG Burner

Installation of Heat Exchanger

Recharging of Primary Loop with proper Ammonia-Water

Solution/concentration

4.2.1 Design of Heat Exchanger

Collect Information from User Manual and Manufacturer, about specific

system conditions which must be known for a proper analysis to be

conducted

Define the required Output Parameters

Define the Problem using an existing Thermodynamics Model

Make Reasonable Assumptions where applicable

Consider Worst-Case Scenario

Determine Required Input Parameters using Existing Thermodynamic

Models and principles

Select Design Type (based on other research and Thermodynamic

Principles)

Create CAD Model

22

Create Simulation

Cross-Compare Results

4.2.2 Design of Solar Collector

Design History Study/Research

Comparative Analysis

Combined-Design Study

Selection/Optimization

Simulation

Construction

Testing/Validation

4.2.3 Design of Plumbing and Requisite System Components

Design Plumbing Network

Design of Additional Coils/Exchangers (maximize efficiency through

thermal recovery/recirculation)

Determine Metering and Throttling Locations

Integral Component Selection

Construction

Bench Testing

23

4.2.4 Reintegration of LPG-NG Burner (Installed in Series to the Heat Exchanger,

integral part of the Plumbing System)

4.2.5 Retrofitting of Absorption Chiller to the Trolley

Space Allocation

Modeling/Mapping of Interior

Static Analysis/Supporting Frame Design

Dynamic/Vibration Analysis (Damper/Isolator Selection)

Installation of Plumbing and Auxiliary Components

“Dry Test” Then connect Absorber

Testing/Validation

24

4.3 Gantt Chart for the Organization of Work and Timeline

(Timeline for Senior Design Organization and Senior Design time frame)

2016

Task Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Project Formulation

Literature Survey

Design Research

Conceptual Design

Analysis & Optimization

Manufacturing

Testing & Validation

Final Design Table 1: Gant Chart, 2016

25

2017

Task Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Project Formulation

Literature Survey

Design Research

Conceptual Design

Analysis & Optimization

Manufacturing

Testing & Validation

Final Design Table 2: Gant Chart, 2017

26

4.4 Breakdown of Responsibilities Among Team Members

(Indicate Each Member’s Major and Support Roles for Each Task)

Task Designated Responsible

Project Formulation Adrian Gonzalez

Literature Survey Adrian Gonzalez, Daniel Pico

Design Research Adrian Gonzalez, Daniel Pico

Conceptual Design Adrian Gonzalez, Daniel Pico

Analysis & Optimization Daniel Pico

Manufacturing Adrian Gonzalez

Testing & Validation Adrian Gonzalez, Daniel Pico

Final Design Adrian Gonzalez, Daniel Pico

Table 3: Division of Responsibilities

4.5 Patent/Copyright Application

The technology being harnessed for this project is not unique or proprietary. This project

is instead a combination of technologies into a system. In the future it may be desirable to

file a patent on the overall system configuration, but until such a prototype is built and

tested, there will not be a need to do so.

27

4.6 Commercialization of the Final Product

If the preliminary configuration of this trolley proves to be promising, it is safe to say that

the future of this project is for it to be applied to various mass-transportation vehicles.

The vehicles may vary in size and operating conditions (climate), and there will need to

be adjustments made which will better facilitate its application to a spectrum of vehicles.

Commercialization is the goal. The first “client” will be FIU, as this technology will be

applied to the CATS Shuttle. Thereafter, the same research will be retrofitted to work

with the “Trolley” buses which provide public transportation to the City of Sweetwater

residents.

4.7 Discussion

Although this phase of the project is still pending testing, the requirements appear

reasonable. The calculations point in the direction of using Ammonia or Lithium

Bromide as the conducting medium, simply because these two options have better

enthalpy than water. However, it is the goal of this project to push away from the use of

rare/harsh materials and to make a vehicle that operates cleanly, using more readily

available substances.

5. Engineering Design and Analysis

5.1 Overview

Create a mounting frame for an object in an open space is not as complex as creating it

for a big Ac unit including a big size duct to be mounted in tiny space in the back of a

small trolley. Therefore, in this project, exact dimensions are tolerances are very critical

28

as well as the manufacturing cost. My design will be based on simplicity, standardized

raw materials and hardware, easy to manufacture, and easy to mount and take off if

needed.

Figure 1: Solidworks Model of Robur Absorption Chiller

29

Figure 2: Solidworks Model of A/C Duct

30

Figure 3: Solidworks A/C Duct installed to Trolley

31

Figure 4: Rear Isometric of Trolley; A/C Installation Location

32

Figure 5: Solidworks "A/C Installed to Trolley"Assembly

5.2 Kinematic Analysis and Animation

5.2.1 Sub-Project Objectives

Below are the objectives of this branch of the project;

Ease of Manufacture

Work within the confines of the allotted space and location within the

Trolley

Avoid the use of Exotic Materials

Utilize Standard Hardware as much as possible

Analyze the Structure of the Trolley to ensure Weight-Bearing

Capacity

Analyze the Structure of the Trolley to ensure Axial Loading and

Shear Loading will be sustained

Low Cost (as much as Possible)

33

5.2.2 Design Specifications

To make the design as simple as possible, I had to make multiple designs and

ask the same question over and over which is: Is the design doable? Is it

mountable? The answer to the question was to create three different frames

and mount them together when they are inside the trolley. Therefore, I created

three frames that I call, Base Frame which seats on the floor and supports the

weight of the Ac unit, Front frame which will be used to hold both the unit

and the duct, and lock them in place during the trolley rides which creates lots

of vibrations, especially during braking moments, and finally, the back frame

which will be responsible for holding the unit against sliding to the back of the

trolley as well as minimize vertical movements when the trolley vibrates

vertically.

5.2.3 Base Frame

The base frame is designed to sustain the weight of the entire unit and duct.

The total weight that it has to sustain is between 300 to 400 lb. Most of the Ac

unit active and heavy components are located in the side that will face the rear

door of the trolley, therefore, the base has to be reinforced in that side. Also,

the frame needs to be fixed to trolley, and the only way to do that is by using

long bolts and fix it the trolley’s long beams that goes from the back to the

front holding the entire trolley’s weight. The beams are separated by 28 inches

and have 2 inches wide which will be enough to drill and thread holes to make

the mounting possible.

34

5.2.4 Front Frame

The front frame is designed to hold both the as unit and the duct placed on top

of it. At the same time, it must hold them from falling and sliding during high

vibrations and braking. The frame will be made by 1x1x1/4-inch L plain bar,

ant it will have two angled supporting bars to sustain and create a counter

force the horizontal forces that tends to push the unit and prevent it from

falling.

5.2.5 Back Frame

The back frame will be holding the ac unit and prevent it from shaking,

sliding, and falling during acceleration. It will create counter forces along

three directions:

Hold the ac unit to the bottom frame.

Create a counter force against side forces and prevent the unit from falling

to the trolley’s side walls.

Create a counter force against the front back forces and prevent the unit

from falling to the back of the trolley’s wall.

Create a vertical counter force to the vertical forces created by intense

vibrations and prevent the Ac unit from vertical displacements.

35

5.3 Dynamic/Vibration Analysis of the System

A moving vehicle generates lots of intense vibrations along all directions, and having an object

mounted inside requires a mount that can handle all the forces. In Fig.1, we can see the amount

of permanent and momentary forces that frames have to counter in order to lock the Ac unit in

place.

Figure 6: FBD of A/C Unit in Trolley

36

5.4 Structural Design

5.4.1 The Base

The base is mainly constructed by a 1x1x1/4 in 1020 Hot Rolled L shape bar.

I selected this type of material because not only offers toughness and rigidity,

it is available at a very good price comparing to lots of other materials. The

beams will be joined be welding only. the design considered the concentration

of weight caused by the different Unit components. The frame is designed to

sit on 8 rubber vibration isolators that will be mounted on the 8 0.5 in holes of

the frame

Figure 7: Base Frame Isometric

37

Figure 8: Base Frame, Top View

Once designed, some static SolidWorks simulations were made on the base

frame and obtained a minimum factor of safety that is close to 2. The

simulation was based on 500 lb. vertical force and 200lb. horizontal forces.

38

Figure 9: Base Frame, Static Loading Simulation

5.4.2 The Front Frame

The base is mainly constructed by a 1x1x1/4 in 1020 Hot Rolled L shape bar.

All the links will be joint by welding.

39

Figure 10: Frontal Support Frame

Figure 11: Frontal Frame, Multi-View

40

Figure 12: Frontal Frame Installed

Once designed on SolidWorks, I ran some simulations using 50 lb. vertical

force caused by the duct, and a 200lb. horizontal force. The factor of safety

came up to be around 4.

41

Figure 13: Frontal Frame, Static Loading Simulation

Figure 8: The Front Frame Static loading Simulation

5.4.3 The Back Frame

It will be made by welding a 1x1x1/4 in L steel bar. It will have square plates

at the end of each column to permit the mounting of rubber vibration

insulators.

42

Figure 14: Rear Frame, Isometric

43

Figure 15: Rear Frame, Front

Based on 200 lb. horizontal forces and 500 lb. vertical forces, the simulation

on SolidWorks gave an estimated factor of safety of 2.9.

44

Figure 16: Rear Frame, Static Load Simulation

5.5 Material Selection

5.5.1 Structural Steel Selection

To build the different components of this frame, I selected to use a 1020 hot

rolled 1x1x1/4 L shaped bar that is available in most of metal stores as well as

a ¼ thick, 1 in wide plain cold drawn bar. The selection was based on metal

properties and its lower cost.

45

Figure 17: McMaster-Carr, Angle Bar Stock

Figure 18: McMaster-Carr, Solid Bar Stock

46

5.5.2 Hardware and Damping Components

Figure 19: Hardware, Nuts

Figure 20:Hardware, Bolts

47

Figure 21: Bushing Stud

48

Figure 22: Dampening Mounts

49

5.6 Component Design/Selection

The Heat Exchanger

The heat exchanger was created by using the data provided in the manual and additional

information supplied by the manufacturer. Using this information and already gathered

measurements, the problem was modeled and proper solutions were applied from University text

books (Incropera, Heat transfer, and Introduction to Thermmodynamics)

The following equations were used;

Ideal Thermodynamic System ∆𝑞𝑖𝑛 = ∆𝑞𝑜𝑢𝑡

The system was considered Ideal.

Net Heat Transfer ∆𝑞𝐸𝑥𝑐ℎ𝑎𝑛𝑔𝑒𝑟 = [𝑞𝑊𝑎𝑙𝑙 + 𝑞𝐿𝑜𝑤𝑒𝑟 𝑆𝑢𝑟𝑓𝑎𝑐𝑒 + 𝑞𝑈𝑝𝑝𝑒𝑟 𝑆𝑢𝑟𝑓𝑎𝑐𝑒] + 𝑞𝐺𝑒𝑛𝑒𝑟𝑎𝑡𝑜𝑟

The change in energy (thermal) of the Heat Exchanger is equivalent to the sum of the energy transferred

away from the system (losses to surroundings) and the energy dispersed to the target vessel.

Linear Heat Transfer 𝑞𝑈𝑠,𝐿𝑠 =−𝑘(𝑇𝐻−𝑇𝐶)[𝜋(𝑟1

2−𝑟02)]

𝑑

This equation was used to determine the losses through the top and bottom surfaces of the Heat

Exchanger. Because the Exchanger is a cylinder, the top and bottom surfaces are flat and therefore, the

corresponding laws for heat transfer through a flat surface are very relevant.

Below is the formula which was used to determine the losses of the Heat Exchanger through the

cylindrical wall.

Radial Heat Transfer 𝑞𝑤𝑎𝑙𝑙 =2𝜋ℎ𝐾(𝑇𝐻−𝑇𝐶)

ln(𝑟1

𝑟0⁄ )

On the following page is a sample of the tables produced from the calculations.

50

Figure 23: Heat Exchanger Analysis

Inner

Temperature (F°) Outer

Temperature (°F) Temperature (°C)Pressure (Bar)

Pressure (MPa)Pressure (PSI)

Temperature(K)Heat Capacity

(Cph) of H2O

(kJ/kg*K)

Heat Capacity

(Cph) of H2O

(Btu/lb_m°F)

Thermal

Conductivity 316

stainless (W/m*K)

Thermal

Conductivity(Btu/hr*

ft*°F)

Outer Wall

Thickness

(in)

Outer Radius

(in)

q_Upper Surface

(Btu/hr)

q_Lower Surface

(Btu/hr)

q_Outer Wall

(Btu/hr)

Total Loss

(q: Btu/hr)

q_Total

(Btu/hr)

Inlet

Temperature

T_ih

Mass Flow:

1000

(lbs_m/hr)

(2GPM)

Inlet

Temperature

T_ih

Mass Flow:

1500

(lbs_m/hr)

(3GPM)

Inlet

Temperature

T_ih

Mass Flow:

2000

(lbs_m/hr)

(4GPM)

Inlet

Temperature

T_ih

Mass Flow:

2500

(lbs_m/hr)

(5GPM)

Inlet

Temperature

T_ih

Mass Flow:

3000

(lbs_m/hr)

(6GPM)

Inlet

Temperature

T_ih

Mass Flow:

3500

(lbs_m/hr)

(7GPM)

Inlet

Temperature

T_ih

Mass Flow:

4000

(lbs_m/hr)

(8GPM)

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261.8584.5525

8.45521226.3320

5352.8965

0.691717.2925

0.0702889930.125

4-41.2581

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605.3394579.8371

564.5357554.3347

547.0483541.5835

512.3330

266.8587.5924

8.75921270.4219

5402.9445

0.703217.3700

0.0706040080.125

4-42.2310

-42.2310-11009.6864-11094.1484

-106094.1484663.2138

612.9192587.7719

572.6835562.6246

555.4397550.0509

521.3330

271.8590.6322

9.06321314.5118

5452.9925

0.714617.4475

0.0709190230.125

4-43.2109

-43.2109-11265.1595-11351.5814

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620.5462595.7422

580.8597570.9381

563.8512558.5361

530.3330

276.8593.6721

9.36721358.6018

5503.0405

0.726117.5250

0.0712340380.125

4-44.1979

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-106610.8616677.1625

628.2183603.7462

589.0630579.2742

572.2821567.0381

539.3330

281.8596.7120

9.67121402.6917

5553.0885

0.737517.6025

0.0715490530.125

4-45.1919

-45.1919-11781.6052-11871.9890

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635.9333611.7825

597.2920587.6317

580.7314575.5562

548.3330

286.8599.7519

9.97521446.7816

5603.1365

0.749017.6800

0.0718640680.125

4-46.1929

-46.1929-12042.5779-12134.9638

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643.6893619.8495

605.5456596.0097

589.1983584.0897

557.3330

291.85102.7918

10.27921490.8715

5653.1845

0.760517.7575

0.0721790830.125

4-47.2010

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651.4844627.9458

613.8226604.4072

597.6819592.6379

566.3330

296.85105.8317

10.58321534.9614

5703.2325

0.771917.8350

0.0724940980.125

4-48.2161

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659.3169636.0702

622.1221612.8234

606.1815601.2001

575.3330

301.85108.8716

10.88721579.0514

5753.2805

0.783417.9125

0.0728091130.125

4-49.2383

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667.1851644.2213

630.4430621.2575

614.6965609.7757

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675.0875652.3981

638.7845629.7087

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593.3330

311.85114.9513

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0.806318.0675

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683.0226660.5994

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602.3330

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4-52.3469

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690.9890668.8243

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640.3267635.5771

611.3330

321.85121.0311

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0.829218.2225

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4-53.3971

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698.9856677.0717

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648.8967644.2008

620.3330

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4-54.4544

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-109305.2622750.3514

707.0109685.3407

672.3385663.6705

657.4790652.8353

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5.6.1 Piping Network Design

In order to satisfy the system’s needs the team will use an accumulator. An

accumulator is a pressure storage reservoir in which non-compressible water

is held under pressure that is applied by compressed air in the other side of the

diaphragm. The accumulator will be able to withstand the incoming pressure

and temperature from the air conditioning unit and pass it along to the solar

collector and provide many advantages to the system. An accumulator is

usually a two chamber spherical tank where divided by a diaphragm is in

between the fluid and compressed air. This compressed air can help during

pressure fluctuations and absorb shocks in the system, such as water hammer.

(http://hydraulicspneumatics.com/200/TechZone/Accumulators/Article/False/

6446/TechZone-Accumulators)

The team will use SAE and NPT standards for all pipe and threads. The

accumulators typically found in off the shelf suppliers such as McMaster-Carr

are all SAE threads, in order to safely move this water at over 3000 psi and

temperatures ranging from 360 to 600 degrees Fahrenheit, the team will use

compression stainless steel tubing in order to prevent leaks and thermal

breakdown of other less capable materials. All these stainless steel tubing and

threads follow NPT standards. Adapters will need to be used in order to

connect all components together.

52

Figure 24: Overall Fluid System Schematic

A steady supply of super-heated water will be coming out of the air

conditioning unit this will pass along a series of check valves and through a

filter before passing by the accumulator. After it goes through the solar

collector the system will pass the tubing by the burner and finally back into

the air conditioning unit. Along the way things like temperature and pressure

gauges can be added in order to verify proper system performance. These can

be remove once the prototype is proven to work and will no longer need to be

constantly monitored.

53

The team chose a 32 oz. piston style accumulator part number 716K52 from

the McMaster-Carr catalog for this project. The reasoning being it is that it is

able to maintain 4000 psi and has the ability to work with superheated water.

304 Stainless steel tubing can handle all of the previously mentioned

parameters for this project. As well as any other fittings that will be required

during assembly of the system.

A flow analysis was conducted by applying Bernoulli’s extended equation to

characterize the water flowing through the system. Bernoulli’s equation

expresses the total energy of a system in the form of head. Fluid head is

essentially represented as a column of water. Given the inputs of the system,

the output pressure of the water flowing into the IDG can be calculated using

Bernoulli’s equation.

The following is Bernoulli’s extended equation expressed in head where z

represents height, v is velocity, P is pressure, ρ is density of the fluid, g is

gravity, Hp is pump head and HL is the total sum of Head loss throughout the

system.

The following is an expression for the combination of major and minor head

losses. Major Head loss is associated with the friction factor f, the length of

the piping L, and the diameter of the pipe D. The minor losses are associated

with the sum of coefficients K which represent the various bends, expansions,

and joints in the network.

54

A full analysis will be conducted to take into account all major and minor

losses, as well as taking into account losses due to temperature, height

differences, and pressure losses in the system.

5.6.2 Solar Collector Design

Renewable energy resources exist over wide geographical areas, in contrast to

other energy sources, which are concentrated in a limited number of countries.

Rapid deployment of renewable energy and energy efficiency is resulting in

significant energy security, climate change mitigation, and economic benefits.

The results of a recent review of the literature concluded that as greenhouse

gas (GHG) emitters begin to be held liable for damages resulting from GHG

emissions resulting in climate change, a high value for liability mitigation

would provide powerful incentives for deployment of renewable energy

technologies. A solar thermal collector collects heat by absorbing sunlight. A

collector is a device for capturing solar radiation (Marken, 2009). Solar

radiation is energy in the form of electromagnetic radiation from the infrared

(long) to the ultraviolet (short) wavelengths. The quantity of solar energy

striking the Earth's surface (solar constant) averages about 1,000 watts per

square meter under clear skies, depending upon weather conditions, location

and orientation.

5.6.2.1 Different types of Solar Collectors

Flat-Plate and Evacuated-Tube Solar Collectors are used to collect heat for

space heating, domestic hot water or cooling with an absorption chiller.

Below is a list of the many types of Solar Collectors

Flat plate collector.

55

Evacuated plate collector.

Comparisons of flat plate and evacuated tube collectors.

Bowl.

Through pass air collector.

Unglazed transpired solar collectors.

WORKING PRINCIPLE OF FLAT PLATE COLLECTORS in FLAT

PLATE COLLECTORS -Sunlight passes through the glazing and strikes the

absorber plate, which heats up, changing solar energy into heat energy. ...

Absorber plates are commonly painted with "selective coatings," which

absorb and retain heat better than ordinary black paint (Trimarchi, 2009).

Figure 25: "Box" Solar Collector (Flat Plate)

56

Figure 26: Typical Operation of Flat Plate Solar Collector

Figure 27:Flat-Plate Solar Collector-Solidworks Model

57

5.6.2.2 Design Specifications

From and estimated overall width of the trolley of 6 feet, and a length of

10 feet, the main dimensions of the thermal collector follow the same

overall dimensions of the trolley. The overall width of the thermal

collector is of 6 feet if seen from the front of the trolley, and the length is

10 feet, if seen from the side. Being that the trolley has an offset elevated

area on the roof; the structure of the system must be in the form of a

parabola. The parabola shape that forms the structure, while following the

main dimensions, has a radius of 120 inches. The approximated surface

area of the structure would be of 61 square feet. The coiled copper piping

on top of the structure which is composed of two identical sections, if

stretched out, each section is of approximately 55 feet. The 8 piping as

well as the structure follows the 120-inch radius that gives it the curved

appearance. The outer diameter of the piping is of 1.5 inches and the inner

diameter is of 1 inch. The approximated surface area that each section of

piping is going to cover is of 23 square feet.

5.6.2.3 Design Considerations

First Design for our Solar collector was using a parabolic shaped glass

covered at the top the reason for selecting this design was, wherever the

sun was located the solar collector would be able to come in contact with

the surface (Marken, 2009). The thermal collector would then have a

copper tubing running from top to bottom and wrapping around its outer

58

surface. A copper pipe represents the most ideal material to be used,

because it does not expand much while facing extreme heat. Also, copper

is known for being a good heat conductor, so the pipe would be able to

absorb an important amount of heat from radiation, therefore increasing by

conduction the temperature of the fluid running through the piping system.

The last reason for selecting copper is that it is easily shapeable, making

the manufacturing process easier to get the shape that we desire.

Second Design was using a flat shaped glass instead of a parabolic shaped

glass because of including a Fresnel lens which helps, the design allows

the construction of lenses of large aperture and short focal length without

the mass and volume of material that would be required by a lens of

conventional design. A Fresnel lens can be made much thinner than a

comparable conventional lens, in some cases taking the form of a flat

sheet. A Fresnel lens can capture more oblique light from a light source,

thus allowing the light from a lighthouse equipped with one to be visible

over greater distances.

Final Design after discussing with the team was to come up with a Flat

shaped glass covered at the top of the solar collector, which had increased

number of coils, which gives more time to liquid to travel from inlet to

outlet.

59

Figure 28:Modified Solar Collector (With Reflectors beneath plumbing)

5.6.3 Pump Selection

A pump is a device that moves fluids (liquids or gases), or sometimes slurries,

by mechanical action. Pumps can be classified into three major groups

according to the method they use to move the fluid: direct lift, displacement,

and gravity pumps. Water pumping capacity of different types of water well

pumps: Single Line Jet Pumps water pumping capacity, models and types.

Definitions of TDH Total Dynamic Head, pump lift, flow rate, capacity.

One-line jet pump:

60

A one-line jet pump can typically raise water from depths of just a few feet

(or "0" depth) to about 25 feet in depth, and at water delivery rates of 4 gpm

up to as much as 25 gpm depending on the variables we list below the well

pump capacity tables shown.

A nice example table of shallow well 1-Line Jet Pump Capacities for 1/2 hp,

3/4, and 1 hp shallow well pumps is provided in the water jet. Jet Pump

Installation Manual and excerpted below to illustrate the factors that

determine well pump capacity. Both of the charts below are for one-line jet

pumps produced by Water Ace. 1-Line jet pumps intended for shallow well

use and made by other manufacturers can be expected to have similar

capacities.

Figure 29: Shallow Well, Pump Capacities

61

Figure 30: Shallow Well, Pump Capacities 2

The Water Ace charts (shown in part above) make clear that the capacity of a

one-line shallow well jet pump to deliver water at a given flow rate varies by

these factors:

The depth of the well (the bottom scale in the two charts)

The pump horsepower (the color codes indicate pump model and

horsepower HP variation)

The well pump model (the right hand table is for the company's more

powerful well pump series of 2-line jet pumps)

The condition of well piping, including pipe diameter, length, number

of bends or elbows

The presumption that the entire piping system has no leaks

2-Line Deep Well Jet Pump:

62

A two-line jet pump can typically raise water from depths of 30-feet to 80-

feet, and at water delivery rates of 4 gpm (gallons per minute) (for a 1/2 hp 2-

line jet pump serving an 80-foot-deep well) to 16 gpm (for a 1 hp 2-line jet

pump serving a 30 foot deep well).

A nice example table of Deep Well 2-Line Jet Pump Capacities for 1/2 hp and

1 hp deep well pumps is provided in the water jet. Jet Pump Installation

Manual and excerpted below to illustrate the factors that determine well pump

capacity. Both of the charts below are for 2-line jet pumps produced by Water

Ace. 2-Line jet pumps intended for deep well use and made by other

manufacturers can be expected to have similar capacities.

Figure 31: Deep Well Pump Capacities

63

Figure 32: Deep Well, Pump Capacities2

The Water Ace charts (shown in part above) make clear that the capacity of a

deep well pump to deliver water at a given flow rate varies by these factors:

The depth of the well (the bottom scale in the two charts)

The pump horsepower (the color codes indicate pump model and

horsepower HP variation)

The well pump model (the right hand table is for the company's more

powerful well pump series of 2-line jet pumps)

The condition of well piping, including pipe diameter, length, number

of bends or elbows

The presumption that the entire piping system has no leaks.

From the calculations made by the team, mass flow rate was 5GPM, according

to that the pump was selected.

64

From the manufacturer’s guide for 5GPM we selected North Star NSQ

Series2V On-Demand Diaphragm Pump with Quick-Connect Ports — 5.5

GPM @ 60 PSI.

6. Prototype Construction

6.1 Overview

A fully functional prototype is to be built using incorporating the absorption chiller into a

passenger trolley. All associated components and required parts must be included for the

system to work properly.

6.2 Description of Prototype

The prototype for this design begins with the trolley that was donated to FIU. A gas-fired

absorption chiller as manufactured by Robur Industries was purchased using a

combination of grant money as well as private donations. A chilled water fan coil as

manufactured by Multi-Aqua was also purchased with private donations. The chiller is to

be modified as previously discussed to operate on hot water in lieu of flammable gas.

This includes fabricating and installing a hot water heat exchanger at the base of the

generator. The chiller is be installed within the trolley, and the hot water and chilled

water piping, as well as the supply and exhaust air, are to be connected to the chiller. The

hot water piping is to run to the solar water heater. The chilled water piping is to be run

to the fan coil. The exhaust air is to connected to the exhaust louvers. Special care is to

be taken that the exhaust exits the vehicle opposite the passenger entry/exit side of the

trolley.

6.3 Prototype Design

65

The prototype for this design begins with the trolley that was donated to FIU. A gas-fired

absorption chiller as manufactured by Robur Industries was purchased using a

combination of grant money as well as private donations. A chilled water fan coil as

manufactured by Multi-Aqua was also purchased with private donations. The chiller is to

be modified as previously discussed to operate on hot water in lieu of flammable gas.

This includes fabricating and installing a hot water heat exchanger at the base of the

generator. The chiller is be installed within the trolley, and the hot water and chilled

water piping, as well as the supply and exhaust air, are to be connected to the chiller. The

hot water piping is to run to the solar water heater. The chilled water piping is to be run

to the fan coil. The exhaust air is to connected to the exhaust louvers. Special care is to

be taken that the exhaust exits the vehicle opposite the passenger entry/exit side of the

trolley.

6.4 Parts List

Trolley (Donated to FIU)

5-Ton Absorption Chiller by Robur

Fan Coil by Mult-Aqua

Solar Water Heating Panel (by another team)

Black Steel Hot Water Pipe

Black Steel Chilled Water Pipe

Armaflex Pipe Insulation

Black Steel Hot Water Heat Exchanger Prototype

Mounting Hardware

Vibration Isolation Pads

66

Intake and Exhaust Louvers by Greenheck

Exhaust Plenum

6.5 Construction

Beginning with the Robur Chiller, the system was disassembled to explore and study the

internal components. Once a design was finalized, the chiller was modified to fit within

the designated space at the back of the trolley. The rear windows of the trolley were

removed to allow for the installation of the supply and exhaust louvers required for the

condenser section of the chiller. Next, the hot water heat exchanger was fabricated to

meet the design specifications. Unfortunately, since there was no solar water heater

available, this component was unable to be tested within the chiller. Instead, simulations

were run to test the functionality of this component. The chiller was then installed within

the designated space. A partition was installed between the mechanical space for the

chiller and the passenger compartment of the trolley. The fan coil was mounted the

partition. The chilled water lines were run from the chiller to the fan coil. Those lines

were insulated using the aforementioned Armaflex insulation to prevent sweating. The

discharge at the top of the chiller was ducted to the exhaust louvers on the side of the

trolley opposite the passenger ingress/egress. Since the hot water conversion was unable

to be tested, the chiller was once again converted to run on flammable gas. The gas

piping was connected to a propane tank to allow for testing of the cooling of the system.

The fan and pump motors were connected to building power since the batteries of the

trolley are not yet installed. Once everything was connected, the system was tested.

6.6 Prototype Cost Analysis

Component Cost

67

Absorption Chiller (5 Ton) $6,500

Water Pumps (2) $1,000

Chilled Water Fan Coil $2,000

Misc. – Piping, Insulation, Wiring $4,000

Total Material Costs $13,500

Labor Costs

160 work hours

5 hours per week x 32 weeks

Average salary for an engineer: $41.31/hour*

Total estimated labor cost: $6,609.60

Total estimated Materials and Labor Costs = $20,109.60

6.7 Discussion

Building of the prototype proved to be more difficult than anticipated due to the project’s

dependence on aspects designed and built by others. In lieu of physical testing of the hot

water heat exchanger, we had to settle for simulations. Fortunately, we were able to test

the other components of the chilled water system. Hopefully, future iterations of the

project will be able to advance our research, build a fully functional prototype including

the solar water heater, and maybe even incorporate some of our alternate designs.

7. Design Considerations

7.1 Health and Safety

Due to health and safety concerns, some aspects of the original design were omitted.

Since the chiller uses Ammonia, which is toxic, as the refrigerant, we were not able

modify the internal piping designs of the chiller without taking unnecessary risks.

68

Instead, the layout was modified to allow for the chiller to be installed whole. Further, all

safety precautions were taken such as wearing work gloves to prevent cuts and burns as

well as wearing safety goggles to prevent injury to the eyes. The work was performed at

the shop of a licensed air conditioning contractor with the supervision of a certified

pipefitter and welder. Also, long pants and long sleeves were worn to prevent injury to

the arms and legs. The work was performed outdoors in a well-ventilated location. As

for the propane burner, again, all safety gear was worn and the test was performed

outdoors.

7.2 Assembly and Disassembly

The chiller by Robur was fairly simple to disassemble and reassemble. The unit was

designed to be easily serviced by a licensed professional. All work was performed using

simple hand tools with the exception of the water piping. This required a pipe threader.

The system will be easy to disassemble should someone choose to continue researching

and testing this product.

7.3 Manufacturability

Considering that the chiller is commercially available, it is quite easy to manufacture this

modified system. However, it would most effective for someone to negotiate with this,

or another, manufacturer to allow for the incorporation of the hot water heat exchanger

design into their product offerings. It is a simple modification to their existing design,

but it can be used for a number of possible scenarios. A unit that is designed specifically

for trolleys would require quite a bit more design as not every trolley has the extra space

in the rear of the compartment. The system would have to be designed from the ground

69

up to fit in a much more compact space, probably beneath the floor of the passenger

compartment.

7.4 Maintenance of the System

7.4.1.1 Maintenance of Chiller

Correct maintenance prevents problems, guarantees maximum operating efficiency of the

appliance and allows running costs to be reduced. Before carrying out any operation on

the appliance, switch it off via the appropriate on/off commands (or via the DDC, if

connected and in controller mode) and wait for the shutdown cycle to terminate. When

the appliance is off, disconnect it from the gas and electricity mains via the external

disconnecting switch (GS) and the gas valve.

Caution: Label all wires prior to disconnection when servicing controls. Wiring errors

can cause improper and dangerous operation. Verify proper operation after servicing.

Any operation that regards internal components of the appliance must be carried out by

an authorized Robur Technical Assistance Center (TAC), according to the instructions

supplied by the manufacturer.

Perform the operations described below at least once a year. An authorized Robur

Technical Assistance Center (TAC) will check the unit for correct operation every two

years. If the unit is subjected to particularly heavy use (for example in processing plants

or in other conditions of continuous operation), these maintenance operations must be

performed more often.

Inspection and cleaning of the flue gas passage:

You will need: the unit shut off

1. Turn off gas and electric supply to the unit.

70

2. Remove front panel.

3. Clean the base pan around the generator housing of any debris.

4. Look at the flue outlet of the generator housing and clear any debris that may be

obstructing the opening.

5. Look at the air intake chute for combustion air and clear any debris that may be

obstructing the opening.

6. Reinstall front door.

7. Turn on gas and electric supply to the unit.

8. Start unit to check for correct operation.

The manufacturer will not accept contractual or non-contractual liability for damages

caused to people, animals, or things due to incorrect installation and improper use of the

unit and also by not observing the indications and instructions provided by the

manufacturer.

7.4.1.2 Maintenance of Fan Coil

Warning:

Disconnect and lockout the power before making any repair or any services.

Sharp edges and coil surfaces area a potential injury hazard. Avoid contact with these.

Maintenance:

Disconnect Power

Ensure no water is moving through the unit.

Remove the batteries from the remote control.

Check Before Operation:

Check if the air filter is installed and the air outlet is not blocked.

71

Connect Power.

Replace the remote control batteries.

Cleaning the Fan Coil Unit

External weekly cleaning is to be done with a dry cloth soaked with fresh water and mild

soap. Avoid using any other type of detergent.

The frame grill with deco panel can be removed. Clean with warm water not over 120ͦ F

and wipe with dry cloth.

Do not use a chemically treated cloth or duster to clean the unit.

Do not use benzene, thinner, polishing chemical, or similar solvents for cleaning. These

may cause surface discoloration, cracks, or deformation.

Cleaning Air Filters

Dirty and clogged filters reduce the cooling efficiency of the unit. It is recommended to

clean the filters once every two weeks.

Open the deco panel by grasping the rounded grooves and pulling towards you.

Hold the tabs of the air filter and raise it slightly. Then pull the filter downwards.

Clean the air filters with a vacuum cleaner or wash with water then dry.

Do not use benzene, thinner, polishing chemical, or similar solvents for cleaning. These

may cause the surfaces to crack or deform.

Install the air filter vice versa of dismantling procedure. The correct filter side is

indicated by words “FRONT” marked on the filter. The “FRONT” side should be facing

you.

7.5 Environmental Impact and Sustainability

72

The potential impact that further development of this project can have on the

environment is extremely promising. The projects looks to help revolutionize public

transportation by breaking down one of the most energy-consuming features and

converting it to run on renewable and/or waste energy. By doing so, the municipalities

will be able to reach and service many more people without increasing the carbon

footprint of the public transport. Further, this system can be adapted to work on many

other modes of transport such as trains, buses, etc.

7.6 Economic Impact

The economic impact of the system is also far reaching. Since the basics of the system

do not rely on expensive materials and/or processes, it should be fairly inexpensive to

implement once a final, compact design is completed. As such, mass production is not a

farfetched idea. Further, as electrification of transportation becomes more and more

popular, alternate solutions to reduce the load on the batteries become more and more

attractive. The savings offered by an air conditioning system that is powered by solar

heat are immense.

7.7 Risk Assessment

There is very little risk in the current design. The only dangerous component is the

Ammonia circulating with the chiller. As the chiller has been located inside the trolley, it

is not subject to risk of damage by impact. Using neoprene isolation pads, the system has

been isolated from the vibrations of the road and, therefore, carries a reduced risk of

failure at the joints.

8. Design Experience

73

8.1 Overview

The experience gained during the design and build of this project was enlightening. In

addition to the theoretical design process, which includes modeling, calculations,

research, and proofs, this project allowed the team to experience firsthand many aspects

of the physical world of mechanical engineering. Beginning with the economic realities

of such a large project, the team was forced to fundraise in order to purchase the

equipment necessary. Further, the team was involved in the structural modifications to

the trolley. In order to complete the piping portions, the team learned how to thread steel

pipe. Also, in order to build the prototype for the hot water heat exchanger, the team

learned about ERW (Electric Resistance Welding).

8.2 Standards Used in the Project

In the United States, there are numerous regulations that apply to refrigerants used in

mobile air conditioners. System designs must meet safety standards from OSHA.

Further, equipment must meet various safety standards from approved agencies such as

UL, which tests equipment for safety in controlled situations. UL standards may have

additional requirements for tested equipment that use certain refrigerants. Many of the

requirements for alternative refrigerants are based on ASHRAE Standard 15, the Safety

Standard for Refrigeration Systems. The EPA recommends that users follow the

requirements and recommendations as specified in ASHRAE Standard 15 in its ruling on

carbon dioxide as an acceptable refrigerant in retail food refrigeration and cold storage

warehouse applications. Changes in ASHRAE Standard 15 have also been used to justify

changes in UL standards. The regulations are listed alphabetically. A number of

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standards were reviewed during the design and construction of this project. Below is a

list of the most relevant and how they were applied to the project.

8.2.1 ANSI/ASHRAE Standard 15: Safety Standard for Refrigeration Systems

The purpose of the standard is to specify the safe design, construction,

installation, and operation of refrigeration systems.

8.2.2 ANSI/ASHRAE Standard 34: Designation and Safety Classification of

Refrigerants

The purpose of the standard is to provide a system for referencing refrigerants

and classifying refrigerants based on toxicity and flammability.

8.2.3 ANSI/IIAR 2-2008: American National Standard for Equipment, Design, and

Installation of Ammonia Mechanical Refrigerating Systems

The purpose of the standard is to guide the design, manufacture, installation,

and use of ammonia mechanical refrigerating systems with industrial

occupancies. The standard applies to any closed circuit mechanical

refrigerating systems using ammonia as a refrigerant.

8.2.4 SAE Standard J2773: Refrigerant Guidelines for Safety and Risk Analysis for

use in Mobile Air Conditioning Systems

This SAE standard enumerates the processes and methods required to prove

the compliance of relevant safety measures for complex technical systems.

8.2.5 ASME B31.8 Gas Transportation and Distribution Piping System

ASME's B31.8 Gas Transmission and Distribution covers the design,

fabrication, installation, inspection, testing, and other safety aspects of

operation and maintenance of gas transmission and distribution systems,

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including gas pipelines, gas compressor stations, gas metering and regulation

stations, gas mains, and service lines up to the outlet of the customer’s meter

set assembly. The scope of this Code includes gas transmission and gathering

pipelines, including appurtenances, that are installed offshore for the purpose

of transporting gas from production facilities to onshore locations; gas storage

equipment of the closed pipe type that is fabricated or forged from pipe or

fabricated from pipe and fittings, and gas storage lines.

8.2.6 ASME B31.5 Refrigeration Piping

ASME B31.5 covers refrigerant, heat transfer components, and secondary

coolant piping for temperatures as low as -320°F (-196°C), whether erected on

the premises or factory assembled.

8.3 Contemporary Issues

Despite the many benefits of using the Solar Heat collection to provide the energy for the

absorption chiller, society today will be reluctant to embrace the absorption chiller en

masse. The inherently low COP of the absorption chiller will dissuade many. Despite the

ability to discount the “free” energy absorbed from the sun (or other waste heat sources)

many designers will continue to pursue the compression system over the absorption

system.

8.4 Impact of Design in a Global and Societal Context

Should the system prove to be practical and wide reaching, the Global and Societal

benefits can be far reaching. With the push toward electrification of all modes of

transportation together with the push toward mass transit over personal automobiles,

engineers must find ways to extend the battery life of these electric vehicles. Other than

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the obvious improvement of energy capacity of the batteries, more efficient systems that

use the energy are just as important. This application of a cooling system that removes

itself from battery dependency is revolutionary.

8.5 Professional and Ethical Responsibility

As engineers, it will be the responsibility of the members of this team to push the

boundaries of design for the purpose of finding better functionality and efficiency.

Further, it is the ethical responsibility of each team member to consider the long-term

ramifications of the design. This project meets both these goals by finding new

functionality and efficiencies for the existing absorption chiller.

8.6 Life-Long Learning Experience

As discussed previously, the team was exposed to many practical processes during the

construction of the prototype. These experiences will go a long way to furthering the

engineering careers of the team members. Further, the research conducted into the many

standards that applied to this project has expanded the horizons of the members and how

design must meet the safety criteria first and foremost.

9. Conclusion

9.1 Conclusion and Discussion

Today, electricity is the most utilized source of energy because of its reliability and

efficiency. There are numerous ways to generate electricity. Despite other, more

environmentally friendly ways, the ways that are most prolific continue to rely on oil,

coal, and natural gas as their main source of energy. However, advances in electricity

generation have led to renewable energy systems, such as the photovoltaic panels, wind

turbines, geothermal, etc., which use naturally occurring energies as a source to generate

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electricity. This electricity must be stored for future use. Energy storage is typically

done via chemical batteries. Battery advancements have allowed for the

commercialization of battery-powered electric vehicles. However, the multitude of

systems that depend on the batteries significantly drain the charge of these batteries

reducing the driving range of the vehicles.

This project looks at how solar energy and solar radiation can be harvested to provide the

heat required to power an air conditioning system that depends on absorption in lieu of

compression. As a result of the electricity being replaced by renewable energy sources

that are being implemented, there is a reduction in the carbon emission due to the

generation of the electricity. This system allows for operation without carbon emission,

and therefore, it produces less damage to the environment. Another beneficial element of

the system is that the use of solar heat allows for the functioning of the unit across many

parts of the world. Unfortunately, this same solar-dependent system fails to work in parts

of the world where solar heat is not consistent. This is why the team explored the

alternate designs for capture of other sources of waste heat.

Renewable energy sources such as solar heat tend are available for next to nothing

EXCEPT for the cost related to the extraction equipment. For this reason, the

implementation of the project stalled due to the cost of the solar water heating panel. The

proposed system uses a panel designed and built by another team, but due to cost, the full

scale model of the water heating panel was never built.

One of the objectives of this project was to create a device that could be easily

implemented into a mass transit vehicle such as the trolley. The team was able to install

the chiller in the trolley, but the design is not compact enough to work in most other mass

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transit vehicles. If the team would have been able to rework the ammonia/water piping

circuit, this goal could have been achieved. However, due to cost and safety

considerations, this was temporarily abandoned.

In spite of the expected obstacles, the team successfully built a system as proposed

allowing for further design of this prototype for demonstration. Further design and

development by future senior design teams can be made to advance the benefits and

drawbacks mentioned above.

As the need for more clean energy sources develops, new efficiencies within existing

technologies are going to play a vital role in the future of engineering. This project has

set groundwork for technological advances that may assist in reducing carbon emissions

as well as improve the quality of life for people throughout the world.

9.2 Evaluation of Integrated Global Design Aspects

The overall Project is a great example of a “Globally Aware” Product. Everything from

the building materials to the heat-transfer medium was selected such that the end result is

a device which is easy to use, relatively low-cost, and easy to maintain. Exotic chemicals,

though ideal for this device, are difficult to contain and handle. They are also very

expensive to refine and install. By using water, steel, and iron, combined with the correct

treatment/processes, the overall design will be reliable and user-friendly.

9.3 Evaluation of Intangible Experiences

Since the system relies on the free energy from the sun, it works best in climates where

abundant solar heat is available and consistent. Therefore, worldwide applications are

not ideal. However, there are numerous geographical regions throughout the world that

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could benefit from this system. As such, the user manual would be available in different

languages including English, Spanish, Italian, Greek, French, Arabic, etc. Programs such

as Google TranslateⓇ can help with this endeavor. These manuals will include

installation instructions, maintenance, replacement parts, etc. The user manual should

include both SI and Imperial units of measure depending on the geographical location.

Further, by using internationally recognized standards, the system can easily be adapted

to work just about anywhere.

9.4 Commercialization Prospects of the Product

The product has far-reaching commercialization possibilities. However, one would have

to find a chiller manufacturer that is willing to become a partner. Currently, the team was

unable to purchase the chiller parts separately. Therefore, a complete chiller was

purchased. This did not allow for optimization of design and layout of the components.

If this obstacle can be overcome, future iterations that include the alternate designs

discussed can be marketed to mass transit manufactures such as BYD who makes electric

buses.

9.5 Future Work

Future work on this project would include implementation of the alternate designs.

Further, with funding from agencies such as DOT, FDOT, MDTA, etc., the full scale

water heating panel can be built for a true test of the system.

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10. References

10.1 Literary References

References Florida Solar Energy Center. (2010, January). Florida Standards for Design and Installation of Solar

Thermal Systems FSEC Standard 104-10. Retrieved from fsec.ucf.edu:

http://www.fsec.ucf.edu/en/publications/pdf/standards/FSECstd_104-10.pdf

Florida Solar Energy Center. (2010, January). Operation of the Solar Thermal Collector Certification

Program, FSEC Standard 101-10. Retrieved from fsec.ucf.edu:

http://www.fsec.ucf.edu/en/publications/pdf/standards/FSECstd_101-10.pdf

Hardesty, L. (2015, June 18). Efficiency Standards for Commercial Air Conditioners Coming Soon.

Retrieved from Energy Manager Today: http://www.energymanagertoday.com/efficiency-

standards-commercial-air-conditioners-coming-soon-0112967/

Marken, C. (2009, November). Solar collectors: Behind the Glass. Retrieved from Home Power:

http://www.homepower.com/articles/solar-water-heating/equipment-products/solar-

collectors-behind-glass

McMaster Inc. (2016). Product Catalogue. Retrieved from McMaster Carr:

https://www.mcmaster.com/#

Not Specified. (2014). Accumulators. Retrieved from Hydraulics and Pneumatics.com:

http://hydraulicspneumatics.com/200/TechZone/Accumulators/Article/False/6446/TechZone-

Accumulators

Rheem Commercial. (2016, November 3). RACA14, RACA15 (2-5 Ton). Retrieved from Rheem:

http://www.rheem.com/product/commercial-package-ac-raca14-raca15-2-5-ton

ROBUR. (2016). Installation, Use and Maintenance Manual.

Shaftel, H., Jackson, R., & Tenenbaum, L. (2016, May 12). Global Climate Change Vital Signs of the

Planet. Retrieved from Climate Change and Global Warming: http://climate.nasa.gov/

Trimarchi, M. (2009, June 24). How Solar Thermal Power Works. Retrieved from How Stuff Works

Science: http://science.howstuffworks.com/environmental/green-tech/energy-

production/solar-thermal-power.htm

U.S. Department of Energy. (2016, October 12). Air Conditioning. Retrieved from Energy.Gov:

http://energy.gov/energysaver/air-conditioning

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U.S. Department of Energy. (2016, October 20). EIA Independent Statistics & Analysis U.S. Energy

Information Administration. Retrieved from Coal:

https://www.eia.gov/coal/production/quarterly/co2_article/co2.html

U.S. Department of Energy. (2016, September 23). Fequently Asked Questions: How much coal, natural

gas, or petroleum is used to generate a kilowatthour of electricity? Retrieved from EIA

Independent Statistics & Analysis U.S. Energy Information Administration:

https://www.eia.gov/tools/faqs/faq.cfm?id=667&t=2

U.S. Department of Energy. (2016, September 6). Frequently Asked Questions. Retrieved from EIA

Indepedent Statistics & Analysis U.S. Energy Information Administration:

https://www.eia.gov/tools/faqs/faq.cfm?id=73&t=11

Unknown. (2016). Threads: A detailed Explanation. Retrieved from Engineerily:

https://www.engineerily.com/1304161-bsp-and-npt-threads-detailed-explanation-

differences.htm

Unspecified, Multiple Organizations. (2016, September 18). COPs, EERs, and SEERs, How Efficient is Your

Air Conditioning System. Retrieved from Power Knot: http://www.powerknot.com/how-

efficient-is-your-air-conditioning-system.html

10.2 Index of Figures

Figure 1: Solidworks Model of Robur Absorption Chiller ........................................................................... 28

Figure 2: Solidworks Model of A/C Duct ..................................................................................................... 29

Figure 3: Solidworks A/C Duct installed to Trolley ...................................................................................... 30

Figure 4: Rear Isometric of Trolley; A/C Installation Location .................................................................... 31

Figure 5: Solidworks "A/C Installed to Trolley"Assembly ........................................................................... 32

Figure 6: FBD of A/C Unit in Trolley ............................................................................................................ 35

Figure 7: Base Frame Isometric ................................................................................................................... 36

Figure 8: Base Frame, Top View .................................................................................................................. 37

Figure 9: Base Frame, Static Loading Simulation ........................................................................................ 38

Figure 10: Frontal Support Frame ............................................................................................................... 39

Figure 11: Frontal Frame, Multi-View ......................................................................................................... 39

Figure 12: Frontal Frame Installed .............................................................................................................. 40

Figure 13: Frontal Frame, Static Loading Simulation .................................................................................. 41

Figure 14: Rear Frame, Isometric ................................................................................................................ 42

Figure 15: Rear Frame, Front ...................................................................................................................... 43

Figure 16: Rear Frame, Static Load Simulation ........................................................................................... 44

Figure 17: McMaster-Carr, Angle Bar Stock ................................................................................................ 45

Figure 18: McMaster-Carr, Solid Bar Stock ................................................................................................. 45

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Figure 19: Hardware, Nuts .......................................................................................................................... 46

Figure 20:Hardware, Bolts .......................................................................................................................... 46

Figure 21: Bushing Stud .............................................................................................................................. 47

Figure 22: Dampening Mounts ................................................................................................................... 48

Figure 23: Heat Exchanger Analysis ............................................................................................................ 50

Figure 24: Overall Fluid System Schematic ................................................................................................. 52

Figure 25: "Box" Solar Collector (Flat Plate) ............................................................................................... 55

Figure 26: Typical Operation of Flat Plate Solar Collector .......................................................................... 56

Figure 27:Flat-Plate Solar Collector-Solidworks Model .............................................................................. 56

Figure 28:Modified Solar Collector (With Reflectors beneath plumbing) .................................................. 59

Figure 29: Shallow Well, Pump Capacities .................................................................................................. 60

Figure 30: Shallow Well, Pump Capacities 2 ............................................................................................... 61

Figure 31: Deep Well Pump Capacities ....................................................................................................... 62

Figure 32: Deep Well, Pump Capacities2 .................................................................................................... 63

Figure 17: McMaster-Carr, Angle Bar Stock ................................................... Error! Bookmark not defined.

Figure 18: McMaster-Carr, Solid Bar Stock ................................................................................................. 84

Figure 19: Hardware, Nuts .......................................................................................................................... 85

Figure 20:Hardware, Bolts .......................................................................................................................... 85

Figure 21: Bushing Stud .............................................................................................................................. 86

Figure 22: Dampening Mounts ................................................................................................................... 87

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10.3 Index of Tables

Table Page

Table 1: Gant Chart, 2016 ........................................................................................................................... 24

Table 2: Gant Chart, 2017 ........................................................................................................................... 25

Table 3: Division of Responsibilities ............................................................................................................ 26

11. Appendices

A. Detailed Engineering Drawings of All Parts, Subsystems and Assemblies

B. Multilingual User’s Manuals

C. Excerpts of Guidelines Used in the Project

(Standards, Codes, Specifications and Technical Regulations; Quotes with references, or

scanned material as appropriate)

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D. Copies of Used Commercial Machine Element Catalogs (Scanned Material)

Figure 33: McMaster-Carr, Solid Bar Stock

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Figure 34: Hardware, Nuts

Figure 35:Hardware, Bolts

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Figure 36: Bushing Stud

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Figure 37: Dampening Mounts

E. Detailed Raw Design Calculations and Analysis (Scanned Material)

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12. Project Photo Album

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