Quote:
Originally Posted by stillsearching
Having seen boattail after boattail, underpans, and all the rest, one question in my head that applies to alot of potential future aeromods is... is there some ideal front shape? How much contribution to total aero does the front end make assuming you've done everything possible to slick down the rest as much as possible?
For instance, would a flat nose cabover semi have any advantage or disadvantage vs a long nosed conventional semi. Would one type of pickup (like the new Fords which are pretty slick for coefficient of drag last I checked) have a big advantage over another type of pickup (like late 90's Dodge Rams which are as horrible as they come) assuming both have boattails, underpans, removing all the barbs you can that cause drag, closing off part of the grill, etc etc.
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If you'll look at the graphics at #515 permalink (I think) of the Aerodynamic Streamlining Template Part-C thread you'll find a drag table for the streamline bodies of revolution.
In only one source,in 39-years have I seen one of these bodies analyzed for 'reverse-direction,'but Fachsenfeld did it.
So in answer to your question,if you designed by reversing the 'Template',with the pointed end forwards,you could get the drag to within 14% of the drag of the tail pointing backwards.
The big question is about 'caveats.'
'Blunt' noses are actually preferred for 'teardrops' traveling in the traditional orientation.
Fachsenfeld makes no mention as to whether or not you could take any liberties with a 'reverse-Template.
If you can't,then the extreme lay-back angle of the windshield would make forward vision impossible.
That's enough to scare me off.
If you do a 'traditional' teardrop half-body as with the 'Template' you've got a chance at Cd 0.10 as with HONDA's Dream 2 solar car of 1993.Their laminar-wing-based Dream of 1996 scored no lower Cd,although they did better with frontal area (although you cannot get in or out of the 'car' in a traditional manner,whereas you can with the 'Template' [see Bochum University's solar racer]).