Since I modeled the Rear Wing and Diffusser in SW, I already ran the simulation.
Show me. I claim BS. I have a hard time understanding how you can get usable results by modeling JUST the rear wing and JUST the diffuser. Ok, the wing I *kind* of get. So you modeled tiny pieces of a larger equation? 1. You need to model the car in stock form, and cut it in half.
2. Run your multiple analysis (40/60/80/100/120mph) + a moving floor + two tires spinning. Wait 4 weeks for your results. Then double (car was cut in half to save computational time/memory use).
3. Model your turbulant energy cloud at 55 - 70% and save for future comparison.
4. Model your diffuser and add it to the car.
5. Run your multiple analysis again, and compare.
This is the only way to achieve accurate results of your 'diffuser'.
6. Model your turbulant energy cloud at 50 - 70% and compare.
(rinse and repeat against each variation of wing, diffuser, sideskirt, etc...) I don't think you've done that at all (clearly).
:I also did the Aero calulations (by hand) to cross check the COSMOS results.
VERY hard to believe. Hand calculating is horrifically painful. Refer to the 892 page book "Fundamentals of Aerodynmics" (3rd Edition) by John Anderson. I can't imagine hand calculating something that could be set up StarCD in one hour and retrieve results in a matter of minutes/hours/days based on complexity.
UNLESS, you did a fairly simple laminar flow over a plate analysis or something similar. That'd be almost useless unless you used the same algorithms Flowworks uses. Besides, why try and validate an industry accepted computer programs results? Makes no sense to me.
:I also use SW & COSMOS to model the port maps and calculate flow velocities. I also model the port modifications to simulate the effects prior to cutting metal. I wont even get into the nuances of Flowworks that makes it the least best choice for use (it is easiest though!). Ok, I'll mention one. The mesh. Cubic meshs are large, error prone and inefficient. Tetrahedral and Polyhedral meshes are idea, especially those whose size is based on proximity to a wall. Ps. I *love* CFD.
Petz #3
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