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Old 05-03-2020, 07:38 PM   #5 (permalink)
M_a_t_t
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Most of these methods are new to me, hopefully I have time to do some reading later. What method (or combination) would you suggest aeromods be tested with? Especially the ones that take awhile to make, such as boattails and the like. Currently the most common method for checking is based on coastdown testing. This provides some actual numbers for comparison, even if they might be skewed, to see if a mod works.

If tuft testing is not indicative of lower Cd, and coastdown testing not reliable* both of which are the least cost to do some testing what would be the next best bang for the buck?

*In one of your other threads you suggested you never had any luck with coast down testing. Could you expand on why you feel that way? I was just assuming unreliability in the data.
Quote:
Originally Posted by JulianEdgar View Post
Coastdowns should never be done coming to a standstill, in my opinion. Why? Because you are then spending too long at speeds where aero drag is basically not relevant - but it potentially adds to the error.

But I have never had any luck with coast-downs - of any sort. And Rob Palin (ex Tesla aerodynamicist) was scathing about them in a recent email to me.
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