Thread: New Product Change Sun 10 blade 70mm
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Old Oct 11, 2012, 07:05 PM
PeterVRC is offline
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Australia, VIC, Melbourne
Joined Nov 2006
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I don't think THRUST is the key here.
More important is Efllux Speed and CFM. And what that pair drive your plane too.
Thrust must come from the volume and how fast it moves.
The volume is not set JUST by the area, because air is made up of molecules that can have their density (of them) altered. So more dense means more 'weight' to their force.

How does someone come up with the idea that CFM by Velocity must always be equal end result 'thrust'??? Because DENSITY of that volume can change.
In a non-compressable liquid the resultant is fixed... but not in a gas.

So I would want to be seeing maths that includes air density...not just ambient air pressure, but pressure AFTER the 'pump'.
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