Senior Project (MET 497) Final Report

Running head: MET 497 FINAL REPORT 1

Purdue University Northwest

College of Technology

Department of Mechanical Engineering Technology

MET- 497 - Senior Project in Engineering Technology

MET 497 Final Report

Advisors: Professor Craig Engle & Professor Lash Mapa

Submitted by: Ahmed Al Dobouni & Majed Noor

Due Date: April 21, 2016

Submitted Date: April 21, 2016

MET 497 FINAL REPORT 2

Abstract

With the increased demand on cooling devices all over the world especially in dry and hot climates, the manufacture companies’ need of delivering cooling devices at affordable prices becomes essential. However, the energy that each cooling device consumes cannot drastically be controlled. Therefore, some manufactures promote the idea of using evaporative coolers as a replacement of traditional air conditioning units due to their reduced consumption of energy. In addition, manufactures promote the idea of using evaporative coolers in dry and hot climates where they operate at their highest efficiency in terms of cooling. The reason for this is that evaporative coolers cool the air through the evaporation of water which is best suited to occur in hot and dry climates by adding moisture to surrounding air that is desired to be cooled; as a result, this would drop the temperature of the air in the specified area that is desired to be cooled. The goal of this report is to demonstrate the way evaporative coolers are designed and built as well as how it can be used as a good guide to design and build one. Additionally, the design team demonstrated in this report how the prototype of the Evaporative Cooler fits the hot and dry weather conditions in Phoenix, Arizona, and confirmed that the projects goals are valid via the testing data.


Contents Page Number

1.0 Introduction…………………...................................................................................................7

2.0 Project Goals……………………………………………………….…………………………7

3.0 Project Specifications……………………………………………….…………………….......7

4.0 Project Deliverables………………………………………………….……………………….8

5.0 Theoretical Background……………………………………………….…………...…………8

6.0 Calculations……………………………………………………………………………….......9

6.1 Average Readings of where the Evaporative Cooler is Desired to be Operated at….10

6.2 Sizing the Fan……………………………………………………………………......14

6.3 Sizing the Cooling Media……………………………………………………………15

6.4 Determining How Much Water the System Requires……………………………….15

6.5 Determining the Cost of Water in Phoenix, Arizona………...……………………...16

6.6 Determining the Electric Cost to Operate the System Per Hour…………………….18

6.6.1 The Cost to Operate the Fan per Hour ………………………...………………18

6.6.2 The Cost to Operate the Pump Per Hour ……………………………………...18

6.6.3 The Total Electric Cost to Operate the System per Hour…………….….….19

6.7 The Total Cost to Operate the System………………………………………………….…19

6.8 The Total Cost to Maintain the System……………………………………………….….21

6.9 Dimensions of the Box…………………………………………………………………...…22

7.0 Project Schedule……………………………………………………………………………23

8.0 Risk Assessment……………………………………………………………………………24

8.1 Differentiating between the capability of either Eliminating the hazard or Balancing

it………………………………………………………………………………………………...…26


9.0 Budget………………………………………………………………………………….….28

10.0 Testing Data……………………………………………………………………………...31

11.0 Conclusion……………………………………………………………………………….34

12.0 References………………………………………………………………………….…….36

13.0 Appendix…………………………………………………………………………………38

Tables & Figures Page Number

Figure 1. How an Evaporative Cooler Operate………………………………………….….…8

Table 1. Average Readings of where the Evaporative Cooler is desired to be operated at…...10

Figure 2. Psychometrics Chart……………………………………………………...…………12

Figure 3. Zoomed Version of the Comfort Zone on the Psychometrics Chart…………….….13

Table 2. How Much Water is Needed to Operate an Evaporative Cooler………………….…15

Table 3. The Rates of the Water Cost Depending on the Month…………………...…………17

Table 4. Average Water Cost in Phoenix, Arizona per 784 Gallons of Water in the Summer

Season…………………………………………………………………………………………17

Table 5. The Operation Cost of an Evaporative Cooler up to 24 Hours…………………...…20

Figure 4. Dimensions of the Box…………………………………….….……………………22

Table 6. Project Management Schedule for the Project…………………...………...…...…...23

Table 7. Risk Ranking Schedule…………………………………………….…………….….25

Table 8. Initial Risk Assessment……………………………………………………….….….26

Table 9. The Control Measures for the Spotted Hazards………………………………...…...27

Table 10. Risk Assessment after Applying the Control Measures……………………………28

Table 11. The Initial Budget of the Project…………………………………………………...29

Table 12. The Adjusted Budget of the Project after Risk Assessment……………………….31


Table 13. The Testing Data……………………………………………………………….….32

Figure 5. Experiment Results………………………………………………………………...33

Figure 6. Exploded View of the Assembly in SolidWorks……………………………...…...38

Figure 7. Detailed Drawing of the Back Case in SolidWorks……………………………….39

Figure 8. Detailed Drawing of the Box in SolidWorks………………………………………40

Figure 9. Isometric View of the System ………………………………………………...…...41

Figure 10. Back View of the System…………………………………………………………42

Figure 11. 3D Side View of the System……………………………………………………...43

Figure 12. 3D View of the Back Side of the System from the Inside of the Box……………44

Figure 13. Exploded View of the System……………………………………………………45

Figure 14. Picture of the Pump……………………………………………………………....46

Figure 15. Picture of the Used Aspen Media……………………………………………...…47

Figure 16. Picture of the Used Fan…………………………………………………….….…48

Figure 17. The Used Plastic Valves……………………………………………………...…..49

Figure 18. Picture of the Used Plastic 90o Elbow Fitting…………………………………....50

Figure 19. Picture of the Used Plastic T-pipe Fitting…………………………………...…...51

Figure 20. Picture of the Used Plastic Tubing Straps…………………………………….…52

Figure 21. Picture of the Used PVC Cement/Primer Combo…………………………...…...53

Figure 22. Picture of the Used Pipe……………………………………………………….…54

Figure 23. Picture of the Used Flow Meter…………………………………………….……55

Figure 24. Picture of the Used Screws ……………………………………………………...56

Figure 25. Picture of the Used Silicone…………………………………………….…...…...57

Figure 26. The Used Electric Switch…………………………………………………....…...58


Figure 27. The Used Power Tool Cord……………………………………………………….59

Figure 28. The Used Teflon PTFE Thread Seal Tape………………………………………...60

Figure 29. The Used Garden Hose Adapter……………………………………………...…...61

Figure 30. The Used PVC Male Adapter………………………………………………...…...62

Figure 31. The Used 1/2 in. PVC Schedule 40 Socket Cap……………………………...…...63

Figure 32. The Used Schedule 40 PVC Reducer Bushing……………………………………64

Figure 33. The Used AMP Ring Vinyl…………………………………………………...…...65

Figure 34. The Used Blue Female/Male Pairs Disconnect…………………………………...66

Figure 35. The Used Grip Fast 1/8" X 1/2" Slotted/Phillips Machine Screws……………….67

Figure 36. Picture of the Used Expanded Sheet……………………………………………...68

Figure 37. Picture of the Used Electric Tape…………………………………………….…...69

Figure 38. Picture of the Used Waterproof Electrical Box…………………………………...70

Figure 39. The Used 4” in Ties……………………………………………………………….71


1.0 Introduction:

The primary goal of this report is to provide specific information about the project that

the design team intended to design and build which is an Evaporative Cooler. The project’s

overview will be discussed through different sections of the report which include; Project Goals,

Project Specifications, Project Deliverables, Theoretical Background, Calculations, Risk

Assessment, Testing Data, and the Appendix. Living in a society where the electrical bills are

high, and the weather is hot as well as dry, designing a cooling device that can reasonably cool

down the temperature of the air while being economical in terms of the energy cost to operate it

becomes essential. Therefore, the design team decided to design and build an Evaporative Cooler

as a Senior Project.

2.0 Project Goals:

This project will be fulfilled by achieving the following goals:

Suitable to operate in a dry and hot climate

Effectively implement and apply what the design team members have learned throughout

their engineering education

Design a prototype that encourages the use of environmental friendly cooling devices

3.0 Project Specifications:

Drops air temperature by at least 10 degrees Fahrenheit

Effectively cools a room with up to 1989 ft3 in volume

Water Reservoir can hold up to 5 gallons of water

The cost of the prototype to design and build (< $500)

Saves up to 50 to 75 % of electrical cost compared to a traditional air conditioning unit (Air & Water, 2015)


4.0 Project Deliverables:

Project Report

Complete design of an Evaporative Cooler

SolidWorks detailed drawings

Fabricate and assemble the Evaporative Cooler prototype

Test the functionality of the designed Evaporative Cooler

Risk Assessment

5.0 Theoretical Background:

The cooling device that the design team intended to design operates based on the

evaporation of water. Hot and dry air flows through a wetted insulation pad (Cooling Media) by

being moved through a fan. The insulation pad wetted by water that would be flowing over the

insulation pad at a precious speed and volume as shown below in Figure 1.

Figure 1. How an Evaporative Cooler Operate

Ref: (Richmueller, 2012)


Some of the water that is sprayed on the insulations pad will evaporate which would

increase the water vapor amount in the air and the unevaporated water is recirculated

continuously. This process occurs without adding any external heat source to the system; as a

result, this will not result in the evaporation of some water as a consequence of being heated up

to the saturation point. Thus, “this indicates that the sensible heat was given up by the air. The

Sensible Heat Change occurs when heat is added or removed from the air and the dry bulb

temperature changes as a result” (Pita, 2012). Based on what was discussed above, the

evaporation of water requires heat, since there is no external heat source added to the system;

therefore, this heat must be obtained from the air that is entering the system which results in

lowering its temperature before it gets blown out by the fan into the surrounding that is desired to

be cooled. It is very critical to note the fact that evaporative cooling process is a constant

enthalpy process. “The reason for this is that there is no heat added or removed from the air-

water vapor mixture” (Pita, 2012). Thus, there is only an exchange of heat within the mixture.

This happens by the sensible heat decreasing and the latent heat increasing by the same amount.

The Latent Heat Change process is the process of adding or removing water vapor to the air

which is referred to as humidification and dehumidification respectively, but in this case it is the

humidification process.

6.0 Calculations:

Please refer to the Appendix which shows the drawings of the parts that were designed

after the calculations for those parts were performed. In addition, the Appendix includes pictures

of all the parts that were used to build the Evaporative Cooler. The calculations that were

performed to build the Evaporative Cooler are as follows:


6.1 Average Readings of where the Evaporative Cooler is Desired to be Operated at

The design team intended to design and build an Evaporative Cooler that would be

suitable to operate at a high efficiency. Therefore, the Evaporative Cooler should be designed

based on the weather conditions in the southeastern region of United States where Evaporative

Coolers operate at their highest efficiency since the weather in this region is hot and dry. Thus,

the design team chose the weather conditions of Phoenix, Arizona to design the Evaporative

Cooler since geographically it is located in the southeastern region of the United States. Please

refer to Table 1 below for the average readings in Phoenix Arizona in the summer from May

2015 to September 2015.

Table 1. Average Readings of where the Evaporative Cooler is Desired to be Operated at

These Readings are for Phoenix, Arizona

Requirements Results Resources

Average Dry Bulb Temperature from May to September of 2015

Month May Jun Jul Aug SepReading 77.2 92.8 93.6 96.3 88.8Average 89.74 Fo = 90 Fo

(Phoenix Weather Forecast and Current Conditions, 2016)

Assumed Drop inTemperature From 10 Fo to 20 Fo

Wet Bulb Temperature from May to September of 2015

Month May Jun Jul Aug SepReading 55.1 61.2 69.5 71.8 67.6Average 65.04 Fo = 65 Fo

(Phoenix Weather Forecast and Current Conditions, 2016)

Relative Humidity from May to September of 2015

(MyForecast, 2015)Month May Jun July Aug SepReading 25 22.5 34 38.5 36.5Average 31.3 = 31


Therefore, the design team will consider the average summer dry bulb temperature in

Phoenix, Arizona to be 90 degrees Fahrenheit for the design purpose of the Evaporative Cooler,

and tried to effectively drop it to approximately between 70 to 80 degrees Fahrenheit. “Dry Bulb

Temperature which has an abbreviation of DB is the temperature of the air as sensed by a

thermometer; however, Wet Bulb Temperature which has an abbreviation of WB is the

temperature of water vapor as sensed by thermometer” (Pita, 2012). The design team only

needed to use the DB and WB temperatures as well as the average relative humidity value in the

summer in Phoenix, Arizona which is approximately 31 as shown in Table 1, to use the

Psychometrics chart which is shown in Figure 2 on page 12. The Psychometrics chart was used

in order to determine what would be the appropriate drop in temperature to bring the air’s

temperature to the comfort zone. The design team used the Psychometrics chart to determine

where the weather condition is in Phoenix, Arizona on the chart, and how much the reasonable

drop in temperature would be as well as the raise in relative humidity be to bring the temperature

of the room that is desired to be cooled to the comfort zone. The design team designed the

evaporative cooler to effectively raise the relative humidity to approximately between 50 to 55 to

bring the weather conditions in the room that is desired to be cooled to the comfort zone.


Figure 2. Psychometrics Chart

Ref: (Pita, 2012)


Please refer to Figure 3 below that illustrates a zoomed version of the comfort zone of the

Psychometrics Chart.

Figure 3. Zoomed Version of the Comfort Zone on the Psychometrics Chart

Ref: (Pita, 2012)


Based on Figure 3 on the previous page the design team needed to raise the relative

humidity to 50%, and drop the temperature to 79 degrees Fahrenheit to bring the weather

conditions in Phoenix, Arizona within the comfort zone.

6.2 Sizing the Fan

The fan’s size of an Evaporative Cooler depends mainly on how many cubic feet of air

the fan can blow per minute which has an abbreviation of (CFM). The CFM of the fan can be

calculated by the following equation:

CFM = ACH x V60

Ref: (Pita, 2002)

Where

CFM: flow rate of air in terms of cubic feet per minute

ACH: number of air changes per hour for a room. The recommended air change per

minute for the south region in the United States is every 2 minutes, so this means 30 air

changes per hour. In fact, “a good rule of thumb is to have 1 air change every 2 minutes

in the southern states” (Bhatia, 2012). Therefore, the design team considered an air

change every 2 minutes based on what is commonly done in the southern states of the

United States

V: Volume of the Room that is Desired to be Cooled,ft3.

V = W x L x H

V = 13 ft. x 17 ft. x 9 ft. = 1989 ft3


Therefore, CFM = 30 air changes1hr

∗1989 ft3∗1hr60 minute

=995 ft3

min, this is the flow rate of the

fan that was used.

6.3 Sizing the Cooling Media

Sizing the area of the insulation is very crucial since it plays a critical role in determining

the cooling efficiency of an Evaporative Cooler. The recommended design velocity of the

insulation should have “a Face Velocity (FV) of between 500 to 550 feet per minute (FPM)”

(Bhatia, 2012). The Face Velocity (FV) = CFM

Area of cooling media (Bhatia, 2012). Therefore, FV

= 955 ft3

min1.9 ft2 =¿524

ftmin , this means that the FV falls in the range of 500 to 550

ftmin and the

insulation face area is 1.9ft2.

6.4 Determining How Much Water the System Requires

Table 2. How Much Water is Needed to Operate an Evaporative Cooler

Wet Bulb Depression

(F)

Saturation Efficiency

0.80

0.82

0.84

0.86

0.88

0.90

0.92

0.94

0.96

0.98

5

0.50

0.51

0.52

0.53

0.55

0.56

0.57

0.58

0.60

0.61

10

0.99

1.02

1.04

1.07

1.09

1.12

1.14

1.17

1.19

1.22

15

1.49

1.53

1.56

1.60

1.64

1.68

1.71

1.75

1.79

1.83

20

1.99

2.04

2.09

2.14

2.19

2.23

2.28

2.33

2.38

2.43

25

2.48

2.55

2.61

2.67

2.73

2.79

2.86

2.92

2.98

3.04

30

2.98

3.05

3.13

3.20

3.28

3.35

3.43

3.50

3.58

3.65

35

3.48

3.56

3.65

3.74

3.82

3.91

4.00

4.08

4.17

4.26

40

3.97

4.07

4.17

4.27

4.37

4.47

4.57

4.67

4.77

4.87


Ref: (Bahaita, 2012) Wet Bulb Depression (WBD): “The difference between the dry bulb (DB) and wet bulb

(WB) Temperatures” (Bhatia, 2012).

Saturation or Cooling Efficiency (SE or CE): “The difference between the entering and

exit dry-bulb temperatures (i.e. range) over the wet-bulb depression” (Bhatia, 2012).

WBD = DB Temperature – WB Temperature

WBD = (90 – 65) Fo = 25 Fo

SE =DBTempreture (out )−DBTempreute (¿)

WBD Tempreture

SE = (90−70 ) F

25F=0.80

Therefore, based on Table 2 the water that is required to be used to effectively operate the

system is 2.5 gallons

hour

6.5 Determining The Cost of Water in Phoenix, Arizona

The water cost was calculated as shown on the next page based on the average outside

weather conditions in the summer season in Phoenix, Arizona which are 90 Fo with a relative

humidity of 31% as demonstrated in Table. 1. The cost of water per gallon was calculated based

on the actual cost of water volume while neglecting the Environmental Charges, Sewer Charges,

and the Monthly Base Service Charge as advised by Lash Mapa, Professor of Mechanical

Engineering Technology at Purdue University Northwest (PNW). The reason for this assumption

is that the used water in an Evaporative Cooler usually gets evaporated in time to the atmosphere

so there will be no need for any of the Environmental, Sewer, and Monthly Base Service charges

to be counted in the cost of water per gallon. Table 3 on the next page shows the cost of the


water depending on the month. “The prices on Table 3 are fixed for each 1 unit (748 gallons)

volume of water or less” (City of Phoenix, 2016).

Table 3. The Rates of the Water Cost Depending on the Month

VOLUME CHARGES (Effective March 1, 2016)

Seasons Inside City Outside City

Low Season:Dec., Jan., Feb., March

$3.06 $4.59

Medium Season:April, May, Oct., Nov.

3.60 5.40

High Season:June, July, Aug., Sept.

4.03 6.05

Ref: (City of Phoenix, 2016)

Table 4. Average Water Cost in Phoenix, Arizona per 784 Gallons of Water in the Summer

Season

Month

Water Cost per 748

gallons of water

May June July August September Average

$ 3.60 $ 4.03 $ 4.03 $ 4.03 $ 4.03 $ 3.994

Since the Evaporative Cooler is only expected to be used in the summer season (May –

September), then the average cost of water in the summer season per 1 unit of water (748


gallons) was calculated to be approximately $ 4 as shown above in Table 4. Therefore, the actual

cost of water per gallon is $ 4

748gallons=$0.0053 per gallon. Based on the previous calculations,

the system consumes approximately 2.5 gallons of water per hour, then the Hourly Cost of Water

= the Water Cost Per Gallon X the Consumed Volume of Water = $ 0.0053 X 2.5 gallons/hour =

$ 0.013/hour.

6.6 Determining the Electric Cost to Operate the System Per Hour

The electric cost to operate the system per hour can be determined using the following

equation: Energy (KWh) x The Electric Cost for each KWh.

Energy (KW/hr) = Power (KW) x Time (hr)

The current average residential electricity cost in Arizona per hour = 11.29¢/kWh.

(Arizona Electricity Rates & Consumption, 2016).

6.6.1 The Cost to Operate the Fan per Hour

Fan Power = 0.25 hp x .75 Kw1hp

=0.19 Kw

Time = 1 hour

Therefore, Energy (KW/hr) = 0.19 KW x 1 hour = 0.19 KW/hr

Thus, the Cost to Operate the Fan per Hour = 0.19 KWh x 11.29¢/kWh = 2.15¢/hr.

6.6.2 The Cost to Operate the Pump Per Hour

Pump Power = 0.033 hp x .75 Kw1 hp

=0.025 Kw

Time = 1 hour

Therefore, Energy (KW/hr) = 0.025 KW x 1 hour = 0.025 KW/hr


Thus, the Cost to Operate the Fan per Hour = 0.025 KWh x 11.29¢/kWh = 0.28¢/hr

6.6.3 The Total Electric Cost to Operate the System per Hour

Total Electric Cost to Operate the System per Hour = the Electric Cost to Operate the Fan

per Hour + the Electric Cost to Operate the Pump per Hour = 2.15¢/hr + 0.28¢/hr = 2.43¢/hr

6.7 The Total Cost to Operate the System

On the next page is the total cost to operate the system up to 24 hours based on the

average summer weather conditions in Phoenix, Arizona which are 90 Fo with a relative humidity

of 31%.

The Total Cost to Operate the System Per Hour = the Total Water Cost per Hour + the Total

Electric Cost per Hour. Based on the findings in the previous pages of this report:

The Total Water Cost Per Hour = $ 0.013

The Total Electric Cost Per Hour = ¢ 2.43 x $ 0.01¢1

=$ 0.024

Thus, The Total Cost to Operate the System Per Hour = $ 0.013 + $ 0.024 = $ 0.037.

Operation Time

Per Hour

Volume of the

Used Water Per

Gallon

Water Cost ($) Electrical Cost ($) Total Cost ($)

2 5 $ 0.026 $ 0.048 $ 0.074


4 10 $ 0.052 $ 0.096 $ 0.148

6 15 $ 0.078 $ 0.144 $ 0.222

8 20 $ 0.104 $ 0.192 $ 0.296

10 25 $ 0.13 $ 0.24 $ 0.37

12 30 $ 0.156 $ 0.288 $ 0.444

14 35 $ 0.182 $ 0.336 $ 0.518

16 40 $ 0.208 $ 0.384 $ 0.592

18 45 $ 0.234 $ 0.432 $ 0.666

20 50 $ 0.26 $ 0.48 $ 0.74

22 55 $ 0.286 $ 0.528 $ 0.814

24 60 $ 0.312 $ 0.576 $ 0.888

Table 5. The Operation Cost of an Evaporative Cooler up to 24 Hours

The above indicated operating cost per day (per 24 hours) for the designed and fabricated

Evaporative Cooler is $0.888 which is 2.7 times less than “the average operating cost of a

traditional air conditioning unit per 24 hours which is $2.374 for a room with up to 2000 ft3 in

Arizona” (All Systems Mechanical, 2016). This indicates that the designed and fabricated

Evaporative Cooler saves up to 270% in electrical cost compared to a traditional air conditioning

unit.

6.8 The Total Cost to Maintain the System

It is advised to replace Aspen Media Pads (Cooling Media Pads) once to twice a season.

(Swamp Tech, 2016). The listed roll of Aspen Media in Table 11 (Budget Table) has the

following specifications:


Width: 2 ft.

Length: 24 ft.

Thickness: 0.083 ft. (1 inch)

Area: 2 ft. X 24 ft. = 48 ft2.

Only 1.9 ft2 of Aspen Media was used as Cooling Media to build the prototype of the

Evaporative Cooler. Therefore, the purchased Aspen Media as shown in Table 11 (Budget

Table) can used for approximately 25 times; in fact, 25 X 1.9 ft2 = 47.5 ft2 which is slightly less

than the area of the purchased cooling media which has an area of 48 ft2 as shown above. If the

Cooling Media will be replaced twice in the summer season, then 252

=12.5, which demonstrates

that the purchased Cooling Media is enough for approximately 12 cooling seasons. The listed

Cooling Media in Table 11 (Budget Table) was purchased for $ 30. Thus, $30

12cooling sessions =

$ 2.5, which is the cost of Cooling Media for each summer season assuming that it will be

changed twice a season.

6.9 Dimensions of the Box

The calculations for the dimensions of the box are demonstrated below:


Figure 4. Dimensions of the Box

Cooling Media Face Area = 1.9ft2

• Cooling Media length =√1.9 ft2=1.4 ft

• Tank height = 4 in x 1 ft12∈¿¿ = 0.333 𝑓𝑡

• Tank Capacity=5 gal x 0.133681 ft3

1 gal=0.668 ft3

• Tank Area = 0.668 ft3

1.4 ft=0.477 ft2

• Box width = 0.477 ft2

0. 333 ft=1.43 ft

• To confirm: 1.4ft x 1.43ft x 0.333ft = 0.667 ft3

7.0 Project Schedule:


The project team followed the shown Project Schedule below. The following Project

Schedule was an estimated schedule for this semester from January 2016 to May 2016.

Table 6. Project Management Schedule for the Project

Task Wee

k 1

Wee

k 2

Wee

k 3

Wee

k 4

Wee

k 5

Wee

k 6

Wee

k 7

Wee

k 8

Wee

k 9

Wee

k 10

Wee

k 11

Wee

k 12

Wee

k 13

Wee

k 14

Wee

k 15

Wee

k 16

Prepare a 3D Model on SolidWorks

Design Work and Drawings Completed

Do the Calculations

Decide the Water Pump

Design the Frame

Design for the Mounting Holes of Fan and Pump

Calculations Completed and Approved

Combing and Testing the Pump Motor

Purchase the Fan, Insulation and the Flow Meter

Fabricating and Machining of Other Parts

Design for the Mounting Holes of Fan and Pump

Assembly and Testing of Parts

Complete Final Testing

Final Report

Presentation

8.0 Risk Assessment:


The initial risk assessment and the risk assessment after applying the control measures

were determined based on the Risk Ranking Schedule that is shown in Table 7 on the next page.

This was done by assigning the severity “Impact” on the x-axis of the schedule and the frequency

“Probability” on the y-axis of it for each hazard, and multiplying the two values. Upon assigning

the appropriate risk level for each hazard, applying the Two Stage Approach for each one of the

found hazards took precedence. This approach included the Eliminate stage as well as the

Balance stage. The Eliminate stage is a stage where an engineer or a safety professional would

work on completely avoiding the hazard, and this can be done by finding alternatives to operate a

device in such a way that would exclude the hazard or design it out. In addition, this should be

done in a way that does not interrupt the designed function of the device. The second stage which

is the Balance stage is usually approached if the first stage does not work for a given device or a

machine. In other words, the second stage is approached if there is no way to completely

eliminate the hazard in a given device or a machine. Therefore, the Balance stage focuses more

on reducing the risk level of the hazard to an acceptable level for a given device or a machine

rather than eliminating it. For instance, this may be done by placing warning signs on devices

and machines to remind users of the potential hazards that a given device might poses. In

addition, the Balance stage can be approached by providing the users of a particular device or a

machinery with training, safe operating procedures, and personnel protective equipment if

needed which are equipment that are worn to reduce the exposure to injuries and illnesses that

might be associated with performing a specific work.

Table 7. Risk Ranking Schedule


Risk Ranking Schedule

Ranking Matrix Combining risk elements of probability (frequency) and impact (Severity)

Ref: (Nakayama, 2015)


Table 8 below indicates the prioritization of the hazards that were spotted in the

Evaporative Cooler from the most critical to the least. This helped to determine which hazards

need to be controlled the most.

Table 8. Initial Risk Assessment

No.

Hazard Probability (Frequency)

Impact (Severity)

Risk Level Risk Range

1. Electrical Shock due water being in contact with electrical cables

5 5 25 Catastrophic

2. Electric shock due to the connected electric cables not properly being

sealed with a proper electric sealant tape at the connection points

4 5 20 Catastrophic

3. Physical Injury due to the moving fan 3 4 12 Serious

4. Electrical Shock due to Turning on the system with wetted hands

4 4 16 Major

5. Electrical Shock due to the pump and the fan cables being loose

3 3 9 Moderate

8.1 Differentiating between the capability of either Eliminating the hazard or Balancing it

Unfortunately, the first stage of the Two Stage Approach which is the Eliminate Stage is

not applicable to any of the spotted hazards in the Evaporative Cooler since none of these

hazards can be designed out. Therefore, the second stage of the Two Stage Approach which is

the Balance Stage was considered to reduce the risk level of the hazards to an acceptable level as

shown on the next page in Table 9


Table 9. The Control Measures for the Spotted Hazards

No. Hazard Solution


Covering the electrical cables with a water proof box will reduce the likelihood of an electrical shock to

occur



The connected electric cables at can be sealed with an electric sealant tape at the connection

points

3. Physical Injury due to the moving fan

Fixing a Fan Guard will assist in limiting the contact between the

moving fan and individuals

4 Electrical Shock due to Turning on the system with wetted hands

Indicate in documentation to dry hands well prior to turning on the

system

5 Electrical Shock due to the pump and the fan cables being loose

The electric cables can be fixed in place using electric cable ties

Table 10 on the next page illustrates the risk assessment (from the most critical to the

least) that was performed after the control measures were applied to the spotted hazards that are

shown above in Table 9. In addition, Table 9 above demonstrates that the applied control

measures effectively reduced the risk level and the risk range for each hazard.


Table 10. Risk Assessment after Applying the Control Measures

No.

Hazard Probability (Frequency)

Impact (Severity)

Risk Level Risk Range


2 3 6 Moderate



3 2 6 Moderate

3. Electrical Shock due to the pump and the fan cables being loose

2 2 4 Low

4. Physical Injury due to the moving fan 2 2 4 Low

5. Electrical Shock due to Turning on the system with wetted hands

2 1 2 Low

9.0 Budget:

Table 11 on the next page shows the Initial Budget of the Project prior to Risk

Assessment. Additionally, Table 12 on page 32 illustrates the Adjusted Budget of the Project

which demonstrates the cost of the purchased items which were used to control the spotted

hazard in the designed Evaporative Cooler


Table 11. The Initial Budget of the Project

Component’s

NameQuantity Vendor Part Number Individual Price Total Price

Fan 1 McMaster-Carr 2058K2 $239.31 $239.31

Cooling Media24" X 288" X 1"

1Indoor

Comfort Supply

3409 $28.99 $28.99

Water Pump 1Little Giant

Outdoor Living

CP3115 $68.48 $68.48

Plastic Valve 2 The Home Depot 032888076334 $2.38 $4.76

Plastic 90o Elbow Fitting 4 The Home

Depot611942038626

$0.28 $1.12

Plastic T-pipe Fitting 1 The Home

Depot 611942038916 $0.54 $0.54

Plastic Tubing Straps 1 The Home

Depot 038561013832 $0.65 $0.65

PVC Cement/Primer

Combo1 The Home

Depot 038753302485 $7.68 $7.68

0.5’’ x 1.0’ Plastic Pipe 1 The Home

Depot 754826200488 $1.41 $1.41

Flow Meter 1 Timers Plus P0550 $10.75 $10.75

Metal Sheets 6Purdue

University Calumet

N\A $0 $0

Welding Cost 6Purdue

University Calumet

N\A $0 $0

Screws 8 Lindy’s ACE 56 $ 0.23 $ 1.84

Silicone 1 Lindy’s ACE 11961 $ 6.49 $ 6.49


Electric Switch 1 Lindy’s ACE 3531266 $ 4.49 $ 4.49

8 ft Power Tool Cord 1 Home Depot 756847000252 $ 9.56 $ 9.56

Teflon PTFE Thread Seal Tape 1 Home Depot 078864178500 $ 0.57 $ 0.57

Garden Hose Adapter 2 Home Depot 098268624885 $ 4.80 $ 9.60

PVC Male Adapter 2 Home Depot 611942038176 $ 0.36 $ 0.72

½ Cap Slip 1 Home Depot 611942038527 $ 0.38 $ 0.38

Schedule 40 PVC Reducer Bushing 2 Home Depot 611942038176 $ 0.58 $ 1.16

AMP Ring Vinyl 1 Home Depot 045686045174 $ 1.98 $ 1.98

Blue Female/Male Pairs Disconnect 1 Menards 3640399 $ 7.69 $ 7.69

Grip Fast 1/8" X 1/2"

Slotted/Phillips Machine Screws

1 Menards 2338505 $ 0.82 $ 0.82

The Total Cost of the Initial Budget = $ 409

Component’s Name Quantity Vendor Part Number Individual Price Total Price

Expanded Sheet

(Fan Guard)3” F Lindy’s ACE 5157961 $ 2.99 $ 8.97

Electric Tape 1 Home Depot 813848010021 $ 0.72 $ 0.72

Waterproof

Electrical Box1 Home Depot 042269006799 $ 13.97 $ 13.97


4” in Ties 1 Menards 3642627 $ 1.25 $ 1.25

The Total Cost of the Adjusted Budget = $ 24.91

Table 12. The Adjusted Budget of the Project after Risk Assessment

The Final Budget = The Total Cost of the Initial Budget + The Total Cost of the

Adjusted Budget = $ 409 + $ 24.91 = $ 436.48

10.0 Testing Data:

The current cold weather conditions in Northwest Indiana during April 2016 makes

testing the functionality of an Evaporative Cooler difficult to perform since the results wouldn’t

be as accurate as the summer when the weather conditions are more close to ones in Phoenix,

Arizona during the summer season. Therefore, the design team raised the temperature of a room

to 90 Fo using the central heating system in the room to make the testing procedure more realistic

and reasonable. In addition, the design team used a room that has a volume of 1989 ft3which is

(the same volume as the room that was initially specified to be cooled by the design team as

shown in the “Project Specifications” section). The testing data is shown below which

demonstrates how the temperature of the room was cooled down with respect to time.

Table 13. The Testing Data

Time (Minutes) Temperature (Fo)

0 90

1 89

2 88

3 87


4 86

5 85

6 85

7 84

8 83

9 83

10 83

12 82

14 82

16 81

18 81

20 81

25 80

30 80

35 80

40 79

60 79

Figure 5 below illustrates the gradual drop in temperature in the room where the testing

was performed. In addition, the graph demonstrates that the drop in temperature remained

constant from the 40 to the 60-minute mark. This indicates that the Evaporative Cooler reached

its maximum cooling efficiency at the 40-minute mark; In fact, the temperature remained at 79 Fo

for 20 minutes.


0 5 10 15 20 25 30 35 40 45 50 55 60 65757677787980818283848586878889909192939495

Experiment Results

Temperature Changes over Time

Time (Minutes)

Tem

pera

tue

(F)

Figure 5. Experiment Results

11.0 Conclusion:

The project team designed an Evaporative Cooler that would cool a room’s temperature

based on the evaporation of water, which is cost effective in terms of the consumption of

electrical power. In fact, Evaporative Coolers can save up to 50 to 75 % of electrical power

compared to traditional air conditioning units (Air & Water, 2015). Evaporative coolers are best

suited to operate in hot and dry climates where the relative humidity is low. Therefore,

Evaporative Coolers cool the temperature of air in a room that is desired to be cooled by

moisturizing it, which would raise the overall relative humidity level in the room. Thus, the

design team chose the weather conditions in Phoenix, Arizona to design an Evaporative Cooler


since it is located in the southwestern region of the United States where the weather is hot and

dry. Upon performing the functionality test, the design team concluded that the Evaporative

Cooler that was designed and fabricated, successfully met the project goals and specifications.

The designed and fabricated Evaporative Cooler was able to successfully drop the temperature of

a room with a volume of 1989ft3 from 90 Fo to 79 Fo which successfully meets the Project

Specifications since the temperature drop was initially assigned to be at least 10 degrees

Fahrenheit. In addition, the above mentioned temperature drop elapsed approximately 40

minutes to be achieved (as shown in the previous page) which is considered to be very

reasonable for an Evaporative Cooler to cool a room with a volume of 1989 ft3 within only 40

minutes. Also, the reservoir of the designed and fabricated Evaporative Cooler was proven via

testing to hold up to 5 gallons of water which was one of the major project’s specifications.

Additionally, the cost to design and build the Evaporative Cooler ended up being $ 436.48 which

is within the initial range of the specified budget which was (< $500). Finally, the design team

confirmed via calculations that the designed Evaporative Cooler saves more than 75% of

electrical cost compared to a traditional air conditioning unit as the Evaporative Cooler operating

cost is $ 0.888 per 24 hours. On the other hand, the daily operating cost for a traditional air

conditioning unit in Phoenix, Arizona is $2.674 per 24 hours. This illustrates that a traditional air

conditioning unit in Phoenix, Arizona consumes electricity 2.7 times more than the designed

Evaporative Cooler which makes the designed and fabricated Evaporative Cooler saves up to

270% in electrical cost compared to a traditional air conditioning unit in Phoenix, Arizona.


12.0 References

Arizona Department of Water Resources. (2015). Residential Home Page. Retrieved on April 14,

2015 from: http://www.azwater.gov/AzDWR/StatewidePlanning/Conservation2/Resident

ial/Residential_Home2.htm

Arizona Electricity Rates & Consumption. (2016). Residential Electricity Rates & Consumption

in Arizona. Retrieved on April 15, 2015 from: http://www.electricitylocal.com/states/ariz

ona/

Air & Water. (2015). Portable Air Conditioners vs. Swamp Coolers - Which is Right for You?

http://www.azwater.gov/AzDWR/StatewidePlanning/Conservation2/Residential/Residential_Home2.htm


Retrieved on March 10, 2016 from: http://www.air-n-water.com/Portable-AC-

SwampCooler.htm

All Systems Mechanical. (2016). How Much Does it Cost to Run an Air Conditioner? Retrieved

on April 15, 2015 from: http://asm-air.com/airconditioning/much-cost-run-air-

conditioner/

Bahaita, A. (2012). Principles of Evaporative Cooling System. Retrieved on March 7, 2015

from: http://www.pdhonline.org/courses/m231/m231content.pdf

MyForecast. (2015). Almanac: Historical Information. Retrieved on September 15, 2015 from: h

ttp://www.myforecast.com/bin/climate.m?city=10899&metric=false

Nakayama, S. (2015). Risk Assessment [PDF document]. Retrieved from: https://mycourses.purd

uecal.edu/webapps/blackboard/execute/content/file?

cmd=view&content_id=_5581596_1&course_id=_196257_1

Pita, G. Edward. (2002). Finding the Infiltration Rate. Air Conditioning Principles and Systems:

An Energy Approach (4th ed., p. 9-169). Upper Saddle River, NJ: Prentice Hall

Phoenix Weather Forecast and Current Conditions. (2016). Temperature Summary (F). Retrieved

on February 2, 2016 from: http://tiggrweather.net/wxtempsummary.php

Phoenix Weather Forecast and Current Conditions. (2016). Average Wet Bulb Summary (F).

Retrieved on February 2, 2016 from: http://tiggrweather.net/wxwetbulbsummary.php

Richmueller. (2012). D.I.Y. Inspired Evaporative Cooler Design for Remote Military

Applications. Retrieved on November 15, 2015 from: https://muellerdesignlab.wordpress.

com/2012/04/di y-evaporative-cooler-design/

City of Phoenix. (2016). Water and Sewer Rates and Charges. Retrieved on April 5, 2015 from:

https://www.phoenix.gov/waterservices/customerservices/rateinfo

https://www.phoenix.gov/waterservices/customerservices/rateinfo

https://muellerdesignlab.wordpress.com/2012/04/20/diy-evaporative-cooler-design/

https://muellerdesignlab.wordpre/

http://tiggrweather.net/wxwetbulbsummary.php

http://tiggrweather.net/wxtempsummary.php

http://www.air-n-water.com/Portable-AC-SwampCooler.htm

http://www.air-n-water.com/Portable-AC-SwampCooler.htm


13.0 Appendix:

Detailed Solid Works Drawings


Figure 6. Exploded View of the Assembly in SolidWorks


Figure 7. Detailed Drawing of the Back Case in SolidWorks


Figure 8. Detailed Drawing of the Box in SolidWorks


Figure 9. Isometric View of the System


Figure 10. Back View of the System


Figure 11. 3D Side View of the System


Figure 12. 3D View of the Back Side of the System from the Inside of the Box


Figure 13. Exploded View of the System


Figure 14. Picture of the Pump

The Pump’s Specifications are as Follows:

Flow Rate: 563 Gallons/Hour

Power: 1/30 HP

Weight: 4.1 pounds

Dimensions: 9.8 x 5.2 x 5 inches


Figure 15. Picture of the Used Aspen Media


Figure 16. Picture of the Used Fan

The Fan’s Specifications are as Follows:

Flow Rate: 1,000 CFM

RPM: 2,650

Power: ¼ HP

Amps: 1.5

Blade Diameter: 10"

Height: 14 5/8"

Width: 14 5/8"

Depth: 3 1/4"


Figure 17. The Used Plastic Valves


Figure 18. Picture of the Used Plastic 90o Elbow Fitting


Figure 19. Picture of the Used Plastic T-pipe Fitting


Figure 20. Picture of the Used Plastic Tubing Straps


Figure 21. Picture of the Used PVC Cement/Primer Combo


Figure 22. Picture of the Used Pipe


Figure 23. Picture of the Used Flow Meter


Figure 24. Picture of the Used Screws


Figure 25. Picture of the Used Silicone


Figure 26. The Used Electric Switch


Figure 27. The Used Power Tool Cord


Figure 28. The Used Teflon PTFE Thread Seal Tape


Figure 29. The Used Garden Hose Adapter


Figure 30. The Used PVC Male Adapter


Figure 31. The Used 1/2 in. PVC Schedule 40 Socket Cap


Figure 32. The Used Schedule 40 PVC Reducer Bushing


Figure 33. The Used AMP Ring Vinyl


Figure 34. The Used Blue Female/Male Pairs Disconnect


Figure 35. The Used Grip Fast 1/8" X 1/2" Slotted/Phillips Machine Screws


Figure 36. Picture of the Used Expanded Sheet


Figure 37. Picture of the Used Electric Tape


Figure 38. Picture of the Used Waterproof Electrical Box


Figure 39. The Used 4” in Ties

Senior Project (MET 497) Final Report

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Transcript of Senior Project (MET 497) Final Report