Quote:
Originally Posted by Thenorm
i've always wondered about modern sedans. the rear glass transition always seems smooth enough. that I bet the air stays attached, even though its sub template and producing a low pressure zone (acting like an airfoil)
And as long as you have a horizontal or convex surface at the end to turn the air flow again and produce a high pressure zone, it might work better than a kamm back.
case in point is the new mercedes CLA which gets an absurdly low Cd and even the prius which is sub-template
So for your car, maybe all you have to do is extend the horizontal of the trunk out closer to template
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*So far,the research has demonstrated that drag minimums are only found with the 'Kamm'-form,or wing section.
*Any geometric interruption along the 'ideal' pathway triggers boundary layer separation,which is exactly what streamlining seeks to eliminate.
*Yes,you can achieve reattachment,but you'll have turbulence,or vorticity,or both,and the kinetic energy of each of these can NEVER be recovered in the form of pressure recovery,leaving a situation of lower base pressure, higher pressure drag,and overall higher drag.
*The drag of Mercedes-Benz latest Cd 0.22 offering can still be cut in half.And it requires Kamm's full monty.
Here is Kamm's personal car of circa 1941,Cd 0.23
Here is a 'dirtier' model (the only surviving car) Cd 0.37 (with compromised belly pan
Here is the Kamm-form with full tail,with Cd 0.12,and less with wheel fairings (as with 2013 Cambridge University Eco Racer,Cd 0.10.
