DIY Wind Tunnel

Sometimes you just have to be impressed by the imagination, creativity, enthusiasm and sheer hard work of some students.

One of our Year 13 Physics students has chosen to study the performance of aerofoils (wing sections) as his practical coursework. He decided that he needed a wind tunnel to do this. So, as a Design and Technology project, he used Computer Aided Design techniques to draw up the plans for his wind tunnel, and then built it himself from this design. The design is imaginative as well as effective, and the construction is to a very high standard (better than some of the commercial equipment we buy from educational suppliers!).

He has a large fan at one end (on the left in this picture), and the air from that is channeled through a wooden funnel into the central chamber, which is constructed of perspex, and then expands out again through another wooden funnel at the right hand end. The material used for the central tunnel allows him to see the aerofoil, which is mounted on a metal pin which protrudes through the base of the tunnel and is supported on a superbly built perspex tower with built in rollers to allow the pin to move freely. The tower sits on a balance which can measure the mass to an accuracy of 1/1000 of a gram. He can access the central section through a series of accurately cut hinged perspex flaps, which allow him to adjust the position of the aerofoil, or change to a different aerofoil. He also uses these flaps to allow him to insert an anemometer to measure the airspeed through the tunnel.

Initial experimentation soon revealed that the fan did not produce sufficient airflow. He therefore turned the operation round, and now uses an industrial strength garden blower to blow air through from the other end (that's the orange device at the right hand end). A further refinement since this photograph was taken is to build a baffle from a bundle of drinking straws, as he believes that some erratic results may be caused by turbulence in the air flow, and he hopes the baffle will reduce this.

Here is a real engineer at work. A delight to see, and I hope that he gets some good results from his investigations.