Department of Mechanical Engineering


Aerodynamics Laboratory – Wind Tunnel Hall

This building house two large wind tunnels that have been designed for experimental investigations of the aerodynamics of a wide range of objects such as sails,wings, cyclists, vehicles, flags, buildings, towers and roofs.

The University of Auckland has access to two excellent wind tunnels, giving staff and students unique opportunities to carry out a wide range of innovative research and testing. These wind tunnels are also available for contract research. More information about the testing capabilities of the wind tunnels and their availability for contract research through Auckland UniServices Limited can be found at www.windtunnel.co.nz.

 

Boundary Layer Wind Tunnel

A new closed circuit Boundary Layer Wind Tunnel was constructed at the Newmarket Campus in 2015. Its test section is 20 m long, 3.6 m wide and 2.5 m high, and it has a top speed of 20 m/s. It is designed as a general purpose wind tunnel and has facilities for testing model buildings in wind engineering studies, the drag and power of cyclists on a special balance/dynamometer, and model vehicles on a moving belt ground plane. It may also be used for measuring the drag of bodies like traffic signs, and the loads and performance of wind turbines. This wind tunnel is the largest and fastest of its type in New Zealand.

For Wind Engineering studies, its long test section enables the wind simulation to be controlled so that a range of scales from 1:100 to 1:600 can be used, and it can simulate the flow above smooth surfaces like water to rough surfaces like cities by suitable combinations of blocks, barriers and spires. Coupled with the 512-channel high frequency pressure system, and several sensitive high frequency force balances, it is a powerful facility for investigating loads, pressures and vibrations on models of buildings and other structures like stadium roofs.

 

Twisted Flow Wind Tunnel

Our primary facility for sail testing is the Twisted Flow Wind Tunnel, which is a large open circuit wind tunnel with a straight duct 20 m long. Blocks and barriers of different sizes may be placed on the floor to control the wind speed and turbulence variation with height of the flow onto the model. The wind tunnel has helped several America's Cup and Volvo 70 designers produce winning designs as it is has special vertical twisting vanes at the duct outlet enabling the direction of the flow in the test section to be varied in a controlled manner with height. In this way the "apparent" wind speed and direction onto the sails which varies with height when a yacht sails through the wind, can be simulated in a wind tunnel test on a stationary model. In its yacht-sail testing configuration, the wind tunnel test section is 7 m wide and 3.5 m high, and has a top speed of 8 m/s. The vanes can be removed and the walls of the wind tunnel duct contoured to give narrower outlets for testing smaller objects at greater speeds. The 3.5 m x 3.5 m square outlet can be used for testing small wind turbines, model vehicles and tall buildings. The 2.5m wide x 3.5 m high outlet is used for tests where higher speeds are required, and in this configuration the top speed is 60 km/h.

Further details describing this innovative twisted flow wind tunnel may be found in the paper "A twisted flow wind tunnel for testing yacht sails" by Professor Richard G.J. Flay, J Wind Eng. & Ind. Aerodyn, 63 (1996), pp 171-182.