Quote:
Originally Posted by arcosine
You should use some updated air-foils instead of the 1930's Dymaxion cross section.
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Abbott and Von Doenhoff warn us about attempting to use 2-dimensional flow sections for 3-dimensional flow in ground proximity.Hucho warns against it as well.
All the performance curves for wing sections are for 'flight conditions,' at altitude,in laminar air,and flight Reynolds number.The tabulated data is invalid for operation in ground proximity.
The other thing about 'laminar' sections,is that the air that a road vehicle encounters is already turbulent and will transition over to a fully turbulent boundary layer at about 20-mph.So unless you limit your speed to below 20-mph,and drive only on windless days,without any other traffic around you,there's no chance that vehicle will ever see laminar boundary flow.Even if it does,you still lose,as skin friction is such a minor constituent of overall aero drag,and the large fineness ratios of the 'laminar' bodies would have high drag if built tall enough for a conventional door-slammer automobile.
Even for Aptera,and all the trouble those folks went to, to capitalize on Dr.Alberto Morelli's (NACA 1948 mathematical model) low drag form,the Aptera failed to achieve as low a drag as Jaray's 92-yr-old pumpkin seed.