Quote:
Originally Posted by ai4kk
As thin as they are, how much different do you think this might make?
One advantage I thought of for mounting them all in a row in the middle of the roof is that at least the rear antennas will be in the dirty air from the front ones...but how much drag does a whip present anyway?
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A quick google search says a cylinder has a drag coefficient of 0.3.
So you need to take your diameter and length of the antenna, multiply them together, multiply them by the coefficient of drag, then multiply that by the density of the air, then multiply that by the velocity squared and you'll get how much force it takes to push the antenna through the air, which can also be translated into amounts of energy per distance (like MPG). Of course that isn't including the losses from the engine.
If you angle the antenna then you take the sine of that angle and multiply that by your result and you should get pretty close although I would guess the greater you angle the antenna the more the coefficient of drag would also change, most likely improving (lowering) a little.
SIN(angle) x diameter (meters) x length (meters) x 0.3 x velocity (meters per second) x 1.225 x 0.5 = Force (in newtons)