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sat March 21, 2011 22:20

external aerodynamics
 
hello sir
whether original model car and scaled down model cd value will be same or different?
i.e
original honda accord car cd value 0.3 and scaled down 1:14 model will have same cd or different?

en51nm March 22, 2011 09:43

There will be a scaling effect with Reynolds number.

To obtain the same Cd you will have to alter other parameters to obtain the same Reynolds number as your full scale case.

Afza April 19, 2011 11:52

Answer
 
Quote:

Originally Posted by sat (Post 300442)
hello sir
whether original model car and scaled down model cd value will be same or different?
i.e
original honda accord car cd value 0.3 and scaled down 1:14 model will have same cd or different?


Same...since it was "coefficient" :)

pritish April 19, 2011 14:01

Quote:

Originally Posted by Afza (Post 304257)
Same...since it was "coefficient" :)

yuppp...it shld be same ! ! !

Martin Hegedus April 19, 2011 15:35

The coefficient of drag will only be the same if the Reynolds number is the same. Any difference due to different Reynolds number will be a function of geometry. I expect less difference for boxy cars than streamlined cars.


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