Quote:
Originally Posted by Sven7
The GM half tonneau is the rear half covered?
What are the Texas Tech Aero Shell and the ITworks double-geometry shell?
How far back does the noted boat tail go? All the way to a point?
Pics, or at least links!  |
The GM 1/2-tonneau is just the rear half.It was tested on a C-10 pickup of Cd 0.535.I had to haul a workmate this morning which required emptying out the cab,and with it my workbook with GM's patent which has a performance curve for different configurations of a tonneau.I'll have it for next time,Sorry!
In 1988,Texas Tech University's Dept.of Mechanical Engineering Aero Lab published an SAE Paper on pickup truck aero.It is here that we're introduced to 'aeroshell' for the first time.In the 'photo-albums' under documents,there is an image of their drag table which depicts the aeroshell.It was good for a 20% drag reduction and 10% HWY mpg.
Itworks is me (Independence Technological Works).When I do public presentations people seem to be attached to officialdom,so I created ITworks to connect with the displays.
My cover simply combined the elevation contour of the Texas Tech Aeroshell with some plan taper to cheat a little extra mpg out of the device.It demonstrated a 13% HWY mpg improvement,which according to GM Aero Lab equates to a 26% drag reduction.
As to the boat tail length,70% = 100% as far as the drag eduction goes,as from 70% on,truncation of this structure is duplicated aerodynamically as a 'phantom-tail.'
Fachsenfeld was doing this.This is what Kamm premised his work on.Alberto Morelli did likewise with the CNR car of 1976-78.
I have the GM patent and I'll try and get it scanned this Saturday.AUTOWEEK carried an article for a Gale Banks GMC LSR pickup which sported the 1/2-tonneau for it's 211-mph run at Bonneville.If it isn't in the photo-album I'll dig that out.
The ITworks aeroshell should be in the photo-album as well,or you can just GOOGLE Phil Knox,for the EV World article by Jessica Savage about the T-100 from a few years back .
Hope that helps!
