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Old 09-11-2013, 03:42 PM   #10 (permalink)
aerohead
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anisotrophy/Rstclosure

Quote:
Originally Posted by julien.decharentenay View Post
I agree with you. My expertise is with software and CFD, not shape optimisation. I was thinking of trying a couple more shapes during the week, but I lack the background to go into it in a lot of details. Add I would love to have others testing my software.



The CFD is based on a steady-state RANS simulation package. The simulation uses a k-omega SST turbulence model - with is quite common, but lacks a number of capabilities (which most 2-equations turbulence models lacks): namely laminar to turbulent transition and anisotropy of the Reynolds stress tensors closure.
I peeked at some online CFD stuff,Imperial College,etc..
' looks like they recognize some contextual limitations with the models,but boy are they advancing the state-of-the-art!
When Wolf H.Hucho was with Volkswagen,they would put a car model in the wind tunnel,use visualization techniques to define the wake,along with velocity and pressure probe survey,then import the car-wake coordinates into the software as an aerodynamic singularity,panelizing the wake right along with the car within the wireframe virtual domain.
This gave them a priori knowledge of the actual 3-D wake with which to include in the numerical analysis for comparison to the empirical measurements found in the tunnel.
The CFD just gets better and better.
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