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Old 01-23-2016, 01:24 PM   #4 (permalink)
aerohead
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don't/grille/wheels

Quote:
Originally Posted by ConnClark View Post
Since they were comparing a digital model to a wind tunnel model both being 1:10 they don't need to scale the air speed.

Also since the model(both digital and wind tunnel) was pretty much a joke when it comes to representing a real car, this was more an exercise in CFD software validation.

If you want to do a real car and get results within about 5% you have to have rotating wheels and have flow through the grill taken into consideration.
*If they want meaningful results,then both CFD and wind tunnel testing must be conducted at supercritical Reynolds number.
*Yes,a cooling system would be nice,but I'm not certain that the effect of the VGs would be remarkably impacted by its presence.
*There's scientific evidence which would dispute the need for rotating wheels to obtain meaningful results.

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For me,the takeaway from the article is that,the investigators don't understand boundary layer theory,and consequently,their testing methodology and results have zero scientific merit.
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