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aerohead · 01-12-2010, 03:36 PM

For a submerged body almost all resistance can come from viscous drag at the "skin," as in a torpedo or submarine.
For automobiles,the contribution of skin friction is on the order of 7-12% of total drag,whereas profile drag is on the order of 55%.
Space utilization basically defines the "size" of a vehicle,and it's surface area.
And for commercial coatings as used on autos,laminar boundary layers cannot be maintained above about 20-mph.
Compliant viscostatic coatings which might produce the diaphramic fluid damping exhibited with shark and dolphin skin could theoretically reduce a car's skin friction,but the weight/inertia penalty might over-shadow any gains.The coating would also be required to survive without ablation,for 100,000 miles of driving.
Consumer acceptance of the skin's "styling" could also prove to be a hurdle.

01-12-2010, 03:36 PM	#3 (permalink)
aerohead Master EcoModder Join Date: Jan 2008 Location: Sanger,Texas,U.S.A. Posts: 16,532 Thanks: 24,520 Thanked 7,436 Times in 4,817 Posts	skin For a submerged body almost all resistance can come from viscous drag at the "skin," as in a torpedo or submarine. For automobiles,the contribution of skin friction is on the order of 7-12% of total drag,whereas profile drag is on the order of 55%. Space utilization basically defines the "size" of a vehicle,and it's surface area. And for commercial coatings as used on autos,laminar boundary layers cannot be maintained above about 20-mph. Compliant viscostatic coatings which might produce the diaphramic fluid damping exhibited with shark and dolphin skin could theoretically reduce a car's skin friction,but the weight/inertia penalty might over-shadow any gains.The coating would also be required to survive without ablation,for 100,000 miles of driving. Consumer acceptance of the skin's "styling" could also prove to be a hurdle.