Helical Wind tunnel

grabcad

Last minute idea for NASA Wind Tunnel ChallengeTo have 3 invidual testing section you need to have 3 independent test section +3 bypass section. an they should have same cross section. Because if nr 1 test section air flow is redirected to the bypass section. then No. 2 and 3 test sections must maintain a constant air flow for the tests in operation.If test chamber should be W4x H4m then then you can use rounded pipe and lemon-like cross-section for minimal material usage. Partitions for 2 chambers are common and this helps to save materialEach test box is in same floor level. its easy to walk between of them and check themGeometrically compact shape is ideal for 3d printing without support material. But you need very very big printer in this case :)