Quote:
Originally Posted by cyclist916
Thanks, that's just what I was looking for. The shape that I'm trying to emulate would be similar to a zeppelin or one of those external fuel tanks that you linked to. Any idea on an ideal length-to-width ratio?
|
If you'll look at the 'Aerodynamic Streamlining Template' thread and look through all of it you'll find some tables from Sighard Hoerner's book,'Aerodynamic Drag.'
In his 1951 Edition you'd be looking for Fig.5.13.'Frontal drag coefficient of three-dimensional bodies,depending upon their fineness ratio.'
You'll find your drag minimum here.
---------------------------------------------------------------------------As far as lift goes,most automobile lift is associated with flow separation.Since Hoerner's bodies are incapable of separation,they will not produce lift as it is commonly conceived.
A note of caution: for bluff body road vehicle aerodynamics you'll need to look at W.A.Mair's boat tail research published in the November,1969,AERONAUTICAL QUARTERLY,PP 307-320.This research will limit your choices for fineness ratios.You can see Mair's work in Hucho's books.