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Old 07-07-2009, 03:55 PM   #57 (permalink)
aerohead
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reference

Quote:
Originally Posted by Bicycle Bob View Post
I'm still waiting for the reference on that "ideal" 2.5: 1 teardrop. My many other sources all say that trying to proceed from 5:1 to 3:1 will almost inevitably cause separation. And what if there is any modification to the forebody shape, for wheels or other practical considerations?
Bob,the reference is from Hoerner,it's from airship hull research.For a frontal area-based drag coefficient,the fusiform body of revolution,with 1/3 forebody,and 2/3 aftbody and thickness ratio(length/diameter) of 2.5:1 has Cd 0.04 in free air.An image of this form appears in Hucho's book and is sourced from Horner's book of 1951,Table-7.2,I believe.I'll try to get this stuff online this coming Saturday.
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