RE: AerodynamicsWell, I am gonna try and take some high speed pix of a falling
rain drop. Since I live in Pahrump, it might take a while to actually find a
rain drop. I have my wife sit on the tall ladder while I try and capture one
from an eyedropper. Will try colored water, alcohol, motor oil or? I do think
that the shape changes some but probably only aorund it's terminal velocity.
If I use a sphere as the shape, then I can get a Drag coefficient and
calculate the speed and the distance it needs to fall for max speed. Stay
tuned...
mayf
----- Original Message -----
From: Albaugh, Neil
To: 'DrMayf' ; land-speed@autox.team.net
Sent: Wednesday, January 15, 2003 8:05 AM
Subject: RE: Aerodynamics
mayf;
While we're at it--- raindrops aren't teardrop-shaped, either!
Regards, Neil Tucson, AZ
-----Original Message-----
From: DrMayf [mailto:drmayf@teknett.com]
Sent: Tuesday, January 14, 2003 4:37 PM
To: land-speed@autox.team.net
Subject: Re: Aerodynamics
Danger, danger, danger...unsolicited opinions coming...warning, etc YMMV,
hit delete now.....
Well, all the hoopla over teardrop shape has me sorta laughing to myself.
First when the idea formed up in thinking like a rain drop falling in free
air. I want ya'll to think about that...free air. Cars are nowhere near free
air. They are close to the ground. Ground effects the shape. A teardrop has
to be cambered (flattened) on the bottom surface to keep the drag
coefficient from growing large. Yep, Cd goes up when the teardrop shape is
close to the ground. Now when you make half a teardrop with a flat bottom
whatcha got? A wing for goodness sakes. What do wings do? They fly. Belly
tanks didn't fly because they have equal lift all around. The old belly tank
was pretty good when it was attached to the airplane because there was
nothing stationary around it like in a vehicle..the ground does not move and
the shape has to shear that air next to the ground. So what shape is the
best? Who knows without CFD or some such..or you can look at Jack's NT788...
mayf
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