Monash University boasts the largest wind tunnel in the southern hemisphere.

With a cross sectional area of 12m x 5m and two fans (five meters in diameter) generating wind speed of 50 meters per second and 1.4 million watts of power, the wind tunnel now has the capacity to test full scale, highly technical production pieces and as such, has attracted custom from areas of testing previously unachievable by conventional wind tunnels in Australia.

The wind tunnel is presently used for wind engineeringand industrial aerodynamics. Primary users include Ford and GMH for car testing and large power stations for dispersion studies.
 

The wind tunnel was conceived by Professor Bill Melbourne, Chairman of the Department of Mechanical Engineering at Monash University. He saw the need for full scale model testing and dispersion studies in Australia and has supervised its construction and the current testing programs. Design was undertaken by Clive Grainger, Senior Research Fellow and Senior Lecturer with Monash University with construction and on going building design by Steve Dunell, Senior Technical Officer.

Professor Melbourne who is also known for his contribution to the Australian Standard in Wind Engineering generated funds for the project approximately eleven years ago and design was commenced a year later by Clive Grainger and Steve Dunell.

Clive Grainger's background in fluid flow machining was very relevant to the design of the wind tunnel and Clive continues this application in his current position as Research Scientist with CSIRO. “The Monash wind Tunnel was designed originally on 2D CAD system, but is now entirely on Cadkey.” Said Clive. “At CSIRO, Cadkey is used constantly for designs and model building. I've looked at many CAD systems in the U.K.,all of which were very expensive. Cadkey's affordability prevents the need for companies to make staff redundant in order to compensate for the costs of implementing a CAD system.” Clive added. “Cadkey's three dimentionality makes it a great tool for all engineering purposes.”

In the last five years the Wind Tunnel has been totally redeveloped in a continual updating process by Steve Dunell. “Cadkey has allowed me to continue the work begun by Clive and design parts which were not in the project originally, like the modifications made for car testing. As it stands now, the Wind Tunnel is completely on Cadkey files.” Steve said

 
“The Wind Tunnel works basically like this,” Steve explained, “Air comes from the fans at the front of the wind tunnel and moves through the testing area at speeds of up to 50m/sec. At the end of the ground floor of the tunnel, the air curves up to the top floor and moves in the opposite direction in a closed circuit. This is what is known as Closed Loop Wind Tunnel. The design allows different tests to be conducted in three working sections, one on the top and two on the bottom floor.”

“The top floor is used for testing models made for studies of dispersion for pollutants in the atmosphere. The room is lined with heating elements to simulate different heat layers that can occur like at the site of a power station. The temperature in this part of the tunnel can be controlled 90 degrees celcius. The instrumentation is mounted on a high tech robot which is full of data aquisition equipment and is operated by remote control from the outside of the tunnel. The resuslts of these tests show the amount of pollutants that would be dispersed into the atmosphere.”

“On the main floor, Ford and GMH conduct confidential testing on new and current models. Car companies are very interested in the noise aspects of the vehicles. We provide testing for noise levels and drag co-efficients for the cars.”
 

“When working with structures” Steve continued, “you design principally to codes. These codes are then often challenged by new theories or ideas put forward by designers on a particular project in regards to the wind loading the structures may incur. For example, a building according to a code may require 20mm glass, but scale models of the proposed building can be made to test the wind loading characteristics of the particular building and it may be found that the pressures on the building are not as high as expected. Consequently, a lesser thickness of glass may be usable. In the case of multi-story buildings, these discoveries can save huge amounts of money, but conversely, certain wind loading situations may show that glass thicknesses need to be increased.” Steve said.

“Recently,” he continued, “we have been testing a huge sun shade to check what effect the wind will have on it if it is attached to the outside of a multi-story building. These tests can be done nowhere else in Australia and without the Monash Wind Tunnel, the company's only option would have been to go overseas. We tested the sun shade with wind speeds of up to 160km per hour.”

 
“At this stage, the wind tunnel is still being completed, so all the money raised from testing is poured straight back into the project. The entry conditions into the high speed section will be improved and a new turntable and dynomometer are currently being fitted.”

“About five years ago I approached Barry Dyson from Specialised Technical Services about providing a 3D CAD system for the remainder of the wind tunnel construction. I didn't know much about CAD packages, but found Barry professional and very helpful in explaining and demonstrating theCadkey package and process of installation.”

“I needed to learn the package very quickly to assist with a particular clients urgent requirements and I had no difficulty in assimilating the package. The ‘add on' software called ‘Extrude' proved invaluable to the project. We did everything with BHP sections and we still use this software combined with Cadkey, FastSOLID, FastSURF, and DRAFTPAK.”

Steve concluded, “I have recently introduced CADKEY into the Model making facility at Monash University so the model makers detail all our models for testing in CADKEY and then transfer them to an NC machine language package, then on to NC machinery for manufacture. Models used in wind tunnel testing have to physically mimic the proposed structure, but sometimes also need to reflect the same mechanical properties (ie: stiffness and tortional characteristics) as the original, such as large bridges, for example. As a result, these models can sometimes take months to build.”

Professor Melbourne said, “The Monash Wind Tunnel is going to be the best in the world for this type of work, because it is a combination of a research facility and commercial testing facility. Most motor vehicle companies only have commercial testing facilities which are limited. Our tunnel is quite superior. We have a number of research projects going on in both working sections of the Wind Tunnel and there are students studying their PHD's and Masters Degrees so these facilities are used very much for research studies.”