Rocket drag coefficient

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turkkusuroket

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Hello guys;

I made analysis from ansys and found the cd=0.0037006761 but i don't know it's true
 

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Reinhard

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This number is too low by at magnitude. You can use RASAero to get a good estimation of the cd. If your number is very different from the RASAero result, something went wrong.

Reinhard
 

Chuck Rogers

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What's your reference area?

RASAero II, and other rocket software, use the max cross-sectional area of the body as the reference area. In fact in RASAero II the rocket reference area is put on all of the rocket aerodynamic data plots. (Something I think is a good practice.)

Your CD looks like the reference area is the surface area of the rocket. Use the max cross-sectional area of the rocket body as the reference area.


Charles E. (Chuck) Rogers
Rogers Aeroscience
 

Buckeye

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You are attempting CFD analysis where dozens of things can go wrong for a newbie. Since the Cd is off by two orders of magnitude, and you are not even aware that is a problem, tells me you should brush up on the basics before going any further.
 
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