Ive done this competition before and we found the following things through cfd testing:
- A very slight concave curve in front of the wheels helps send the air over the wheels efficiently.
- For the part of the wing not in front of the the wheels a narrow convex nose should be used.
- If rules allowed, a gentle bulge under the front wing in front of the wheels can deflect air around them.
- The front wing should be narrower at the front compared to the back so as to ease air outwards.
- The inner hub caps could expand out to fill the gap between the body and wheel so no air gets in that gap. Just make sure this extended hub cap doesnt make contact with the body. (3d print it)
- Making your hub caps bulge out reduces area or turbulence on the side of the wheel and improve efficiency.
I'd reccomend doing comparative tests via CFD(floworks) to see if these work with your design.
Ive attached the bulge hub caps test we did.
Sean Cleary