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Old 01-04-2021, 11:19 AM   #9 (permalink)
Vman455
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Quote:
Originally Posted by freebeard View Post
My reading of Figure 16 had Cp-X only negative at 15° yaw and only through the front wheelwell area, not forward of it.


The key here is the slope of the line, which tells you how drag varies (and how much) with length. From the rounded corners back, at both 0 and 15 degrees, the negative slope shows that the x-component of pressure is negative (i.e. it's producing thrust). You can see this in Fig. 14, where the large green area on the body in front of the wheels shows a negative (i.e. forward-directed) x-component of pressure.

Quote:
Originally Posted by freebeard View Post
I'm trying to figure out the significance of Figures 14 and 15. I can see separating out the X and Z vectors, but the blue bottom in 15. — is that a ground interaction?


Perhaps, but this figure doesn't actually tell us that. It shows that there is a negative z-component of pressure over much of the underside, but it doesn't say why (and I don't believe the authors say either).
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