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aerohead · 08-23-2012, 07:18 PM

The bigger challenge is the 'verisimilitude',where the model has the proper Reynolds number,as boundary layer conditions which determine Cd must match the full-scale car.
At around 20 mph,the Cd will be constant for a 1:1 scale car.
*40 mph @ 1/2-scale
*80 mph @ 1/4-scale
and so on.
The model's frontal area cannot be more than 5% of the test section cross-sectional area.
It takes a big powerful blower to make all this work.

08-23-2012, 07:18 PM	#4 (permalink)
aerohead Master EcoModder Join Date: Jan 2008 Location: Sanger,Texas,U.S.A. Posts: 16,363 Thanks: 24,463 Thanked 7,401 Times in 4,795 Posts	bigger challenge The bigger challenge is the 'verisimilitude',where the model has the proper Reynolds number,as boundary layer conditions which determine Cd must match the full-scale car. At around 20 mph,the Cd will be constant for a 1:1 scale car. 40 mph @ 1/2-scale 80 mph @ 1/4-scale and so on. The model's frontal area cannot be more than 5% of the test section cross-sectional area. It takes a big powerful blower to make all this work.