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        Discussion What is the Velocity of the pumped air in an EDF?

#1 Texas Buzzard Oct 11, 2012 06:39 PM

What is the Velocity of the pumped air in an EDF?
 
I am using an E-Flite DeltaV 15 EDF on 3S Lipo and it Absorbs 300 Watts from the Lipo. E-Flite says the velocity of the air in the tailpipe is 71 mph.

Is there a mathematical method of calculating the exhaust velocity from knowing the Watts and the density of air? Is another factor needed?

The density of air is 1.29 gms per liter.

#2 PAPE Oct 11, 2012 09:50 PM

There is no formula for this, only tools to measure it. and your exhaust velocity ( efflux ) is changed by your exhaust tube exit diameter.

For more info on this look at the last couple of pages of the Change sun 10blade 70mm fan.
There is a bunch of engineers talking about that right now.

#3 bwoollia Oct 11, 2012 10:05 PM

Check out some of these threads:

http://www.rcgroups.com/forums/showthread.php?t=1742680

http://www.rcgroups.com/forums/showthread.php?t=1714461

http://www.rcgroups.com/forums/showthread.php?t=1678541

http://www.rcgroups.com/forums/showthread.php?t=1671987

http://www.rcgroups.com/forums/showthread.php?t=1474158


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