TechTalk Issue 72
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Newsletter Number 72
...the result wasa highly effi cientnew product for
car park ventilation.
Victorias largest bulky goods development is now open to the public. Located on a busy intersection in Melbournes southeast, the Springvale Homemaker Centre features Swedish furniture sensation IKEA and Australian retail giant Harvey Norman.
The northern portion of the eight hectare site is dominated by a 32,000sqm IKEA store, the second largest in the Southern Hemisphere, while the southern end has Victorias largest Harvey Norman outlet and 28 other retail stores. In total there is more than 70,000sqm of retail space spread over two floors and two levels of undercover parking for 2,700 cars.
We all thought the IKEA Richmond store was big, but the one in Springvale is 35% larger and is enormous, Allstaff Airconditioning Engineering Manager Haydn Walsh said. There are more than 1,000 products displayed in over 60 room settings in the showroom, and the market hall is almost 7,000sqm.
Allstaff was responsible for the mechanical services of the entire complex and began working on the project in May 2010. Haydn said working with Probuild Construction helped the project go very smoothly even though it was such a large building complex. A lot of thought went into the selection of fans for the car park, he said. Although above ground, the two sublevel car parks were partially enclosed to fit in with the stylised facade and building size. This presented some problems because the developers didnt want to use a traditional car park supply and exhaust system.
There were multiple issues with the electrical requirements and installation, so Peter Cotterell
IKEA & Harvey Norman
from Fantech put together a team to find a solution. Fantech redesigned the JetVent fan to meet the specific requirements of this project, the result was a highly efficient new product for car park ventilation.
Known as the JetVent EC fan, it incorporates an EC (Electronic Commutation) motor with integrated speed control. This allows digital communication between fan units and the BMS.
Haydn said the system includes sensors in the car park to measure the level of carbon monoxide. The BMS receives feedback from the sensors and automatically adjusts the speed of the fan to ensure carbon monoxide levels remain at an acceptable level. This means the fan produces more thrust when there are lots of cars using the car park, but when carbon monoxide levels are low, the fan slows down, which means they use less energy.
Allstaff installed 94 JetVent EC units in the car park, a number of large smoke exhaust fans and various Fantech exhaust fans for the toilets, kitchen and loading dock areas.
Haydn said the IKEA store had been designed by BSE Consultants and incorporated a number of green initiatives. For example, the cooling system has a unique chiller which uses cold condensed water to provide refrigerant-free cooling with minimal electricity input. The water is cooled to 4C at night using the low ambient conditions and off-peak electricity. During the day the chilled water is reticulated from the fire sprinkler tanks, via heat exchangers to the air handling units and through chilled beams, he said.
IKEA opened its doors in September 2011, with the remainder of the centre opening the following month.
D D 2D Fan
33 1 2
3 3D 3
Technically Speaking SEF = 0.6CV (at 1.2 kg/m density).WhereSEF = System effect factor in Pa.V = fan inlet velocity in m/s.C = System Effect Coefficient.
We will determine the losses for an AP1004CA6/25 fan selected to meet a system duty point of 14000 L/s @ 280 Pa.
V = 17.8 m/sAMCA 201-02 (r2007) suggests that the System effect coefficient (C) for the inlet bend installation is 0.4.
Therefore SEF = 0.6CV = 76 Pa.
By determining the system effect pressure loss at multiple points we can show the effect on the fan performance curves.
Graph: Fan performance curves with and without system effect.
As the performance will be the intersection of the system curve and the reduced fan curve, we can see that we would in reality only achieve 13230 L/s @ 252 Pa with this system.
To achieve the desired airflow of 14000 L/s @ 280 Pa we would need to add the 76 Pa system effect to our selection pressure (280 + 78 = 356) and then reselect the fan.
The new selection is an AP1004GA6/28 (we have had to increase the pitch angle of this impeller by 3 degrees to achieve the required pressure). The power consumed will also be at this increased pressure drop.
Therefore we can see that the system effect factor is adding 10.51 8.66 = 1.85 kW of power consumption, or 21%.
On a system running 10 hrs/day, 300 days/yr and at a cost of $0.16/kWh the annual saving would be $888.00.
With the average working life of most fans being 15 years, this would make a total saving of $13,320 over that time. As this fan has a budget cost of $4,352, the electricity saving would be 3.06 times the initial purchase price.
In addition the fan with the ducted installation will produce 5.8 less tonnes of Carbon Dioxide emissions per year which is a total of 87 tonnes over the 15 years (Australian average data from Australian Institute of Energy).
with Kerry Dumicich
Want to improve your
In the first part of this technically speaking series we looked at how increased pressure drops caused by system effect influences power consumption. This edition will look at System effects again, and how they change performance and energy consumption due to a less than optimum inlet condition.
When a fan is tested to ISO 5801:1997 Industrial fans - Performance testing using standardized airways, it is installed in a setup that simulates typical installations. These installation simulations are Type A, B, C, and D as shown in Figure 1. A System Effect is simply the effect on fan performance from the systems connection to the fan, and will allow the user to predict the changes in performance from the tested installation compared with the actual installed condition of the fan.
Figure 1: Installation Types.
In this example we will consider an adjustable pitch axial fan. This style of fan is tested in a Type D configuration. ISO5801:1997 requires that the inlet duct is a straight duct section 4 fan diameters long, and the discharge duct is 6 fan diameters long with a flow straightener 2D from the fan discharge. The flow straightener is required to ensure that the discharge measurement plane is free from swirl which will give more accurate measurements.
Figure 2: Ducted Inlet and outlet requirements from ISO5801:1997.
In this article we will consider an axial fan as tested (with a straight ducted inlet), and compare it to the same fan with a right angled bend hard on the intake.
AMCA Publication 201-02 (r2007) Fans and Systems suggests that the system effect of an installation that deviates from the tested condition can be calculated with the following formula. It is important to note that these numbers are to be used as a guide only, as differences in fan construction will change these factors.
Uniair moves to a bigger offi ce at Coffs HarbourWant to reduce a fans energy
consumption? Part 2.Heres some more low hanging fruit
Absorbed Power (kW)
Input Power (kW)
AP1004GA6/25 7.88 91 8.66 27.3
AP1004GA6/28 9.57 91 10.51 33.1
Table 1: Impact of system effect on power consumption.
TYPE AFree inletFree outlet
TYPE BFree inletDucted outlet
TYPE CDucted inletFree outlet
TYPE DDucted inletDucted outlet
4 4 4
D D 2D Fan
3 1 2
3 3 3
8.0 9.0 10.0 11.0 12.0 13.0 14.0 15.0 16.0 17.0 18.0
- Volume Flow, m/svq
Reduced performancecurve due to system effect.System Curve
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Fans by Fantech Product Selection Program
Uniair moves Uniair moves to ato a bigger bigger offi ce offi ce atat Coffs Harbour Coffs Harbour Tip Tip No.12:No.12:
Selecting for Non-Standard Altitudes and TemperaturesOn the Select Fans screen, you have the option of nominating the temperature and altitude that your fan will be running at.
When calculating the required static pressure, air density, and therefore temperature and altitude, is a key factor. The standard air density of 1.2 kg/m is based on 20C and 0m (sea level).
If your pressure calculations are based on standard air density, there is no need to change the default altitude or temperature, as your fan will be selected at standard air density.
If your pressure loss calculations are based on a non-standard temperature (ie. not 20C) you will need to check the Adjust
pressure for non-standard temperature checkbox and enter the relevant temperature. For a non-standard altitude (ie. not 0m), simply enter the altitude you used in your calculations. This will change the fan selection pressure to match your calculations.
For smoke-spill applications, you should refer to Tip #10.
Architecture by i2C Design & Management
...its speed runs according to the demand in the carpark.
DCVLess than three years after opening an office in Coffs Harbour, Newcastle