Quote:
Originally Posted by skyking
I'm getting there. I just found an old casio solar powered scientific calculator; I had to "borrow" my wife's sewing light to get it going 
That seems a meager start to me. I was hoping to reduce that some more.
Will it work OK open-ended?
I am looking at folding it twice, that would get me out to 13' or so.
If I'm not building a long radius, 12 degrees is absolute the max I should go? |
skyking,it's more about degree of curvature than it is angles.That's why I put the 'Template' together.
If you can't do curves,then consider Walter E.Lay's research of 1933.
He did a 'pumpkin seed car(like Jaray,MG EX-181,GM Solaraycer ),only he did no curves on most of his models.
He had an 18-degree angle for the roofline,and the sides angled in @ 12-degrees.This looks to be about what GM has done with its 'OPTIMUM' boat-tail.
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Lay's models achieved the following drag coefficients as a function of boat-tail length:
* 0% = Cd 0.326
* 10%= Cd 0.325
* 20%= Cd 0.305
* 30%= Cd 0.235
* 40%= Cd 0.187
* 50%= Cd 0.157
* 60%= Cd 0.140
* 70%= Cd 0.127
* 80%= Cd 0.122
* 82.4%= Cd 0.12 ( his 100%template only goes to 82.4% 'Template"
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If you have to do a simple construction this may give you a sense of what's been done with good effect.