Quote:
Originally Posted by sheepdog 44
How long is the template aft body? Could you estimate the Cd with the length of the aft body at 100%, 87.5%, 75% 62.5% 50% etc?
So people can see exactly what can be gained by adding another foot to their car. I'd like to know what length is needed to go "all out" and adjust for what i'm comfortable with. Maybe people would go for a complete aft body if they knew what it required and the benefits over a short Kammback.
|
There are numbers out there somewhere but no tellin' where,so I'll put some up.
If you'll take some graph paper you can construct a curve from which to extract discrete values for any length:
*0% = Cd 0.503
*10% = Cd 0.39
*20% = Cd 0.314
*30% = Cd 0.255
*40% = Cd 0.209
*50% = Cd 0.177
*60% = Cd 0.153
*70% = Cd 0.14
*80% = Cd 0.133
*90% = Cd 0.13
*100% = Cd 0.13
-------------------------------------------------------------------------
From the 'Template' you'll notice that some of the length is lost to ground clearance and also that there is no appreciable drag reduction for tails extended beyond about 80%,as the 'phantom' tail is beginning to operate at this point,with the wake itself acting as a solid boundary for the active outer flow.
--------------------------------------------------------------------------
With wheel fairings the Cd can be lowered a bit more.
