Quote:
Originally Posted by Vman455
Here's what Hucho actually presented when talking about Mair's research (emphasis in original text!):
(Hucho, W.H. "Aerodynamic Drag of Passenger Vehicles." In Aerodynamics of Road Vehicles, 4th edition, W.H. Hucho, ed. [Warrendale: SAE, 1998], 164).
Note the caveats; he doesn't give a blanket "go/no go" because there is no blanket "go/no go"--it depends on the shape and features of the particular car in question, not some hypothetical ideal.
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1) so remove the constant-diameter cylindrical section.
2) join the nose and tail section to form the streamlined body of revolution.
3) use Hucho's drag table from Hoerner to ascertain the Cd of the streamlined body you've just created.
4) subtract out the skin friction no longer present from the elongated body.
5) bifurcate what's left, longitudinally, to create the half-body.
6) double the Cd of the streamlined body to get the drag of the half-body.
7) now add wheels, and wheel drag, as Jaray and Buchheim did, and tell me what you come up with.
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Once the detail optimization is accomplished with the forebody, the flow there is 'saturated', no additional drag reduction is left.
The rest of the story involves the aft-body, given the caveats listed by Hucho which qualify the boat-tailing performance, and for exactly the reasons Hucho spelled out.