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Old 04-11-2011, 07:19 PM   #74 (permalink)
3-Wheeler
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Quote:
Originally Posted by aerohead View Post
Bear in mind that in streamlining,we're dealing with pressure,not inertia and momentum.
Pressure converted to velocity by dislocation will seek equilibrium,flowing towards regions of lower pressure until de-dislocated,at which time it will return to pressure either by streamlining or viscous attrition.
Hi Aerohead,

I'm not sure that I completely agree with what you said about "pressure" being the only factor in air movement.

Air molecules *do* have mass and because of that also have inertia.

Now the air molecule's mass is very low, but it's still there.

Regarding moving an object through the air, the biggest factor is pressure itself and the fact that the molecules "communicate" with each other at only the speed of sound, and not faster like electrons do in electrical circuits.

Air moving close to the speed of sound becomes a major issue because as you know, the "communication link" between molecules is almost nil due to the high speed. The air molecules can not communicate their localized pressure to surrounding molecules, because they are all moving at the speed of sound, and this is as fast as the pressure pulse in the air can move.

Obviously your Streamlining Template is designed to give the air time to move back into it's originally undisturbed space before our vehicle passes through, via the localized air pressure at the time. And this is partly due to particle mass, local pressure, and the speed of sound, all contributing to the general movement of air back to it's original state.

Jim.
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