Aubrey Thompson wrote:

Rotary Engine wrote:

Does anybody know what units are in for air density in this formula
if V is in feet per second. I'll settle for the metric units.

I think it is in pounds per cubic inch which
is .000046676 under standard conditions.


Paul Lamar ...No rotor no motor.

The Rotary Engine NewsLetter. Powered by Linux.
ACRE NL web site. http://www.rotaryeng.net
Copyright 1998-2006 All world wide rights reserved.


------------------------------------------------------------------------

Paul,
This would be the mass density which has units of  [slug]/[ft]**3.  The units for a slug are:  [lb sec**2]/[ft].  Putting these together then gives the mass density in basic units as:  [lb sec**2]/[ft**4].

As I recall, the weight density of air is:  .075 lb/ft**3. Dividing by "g" gives the mass density of air as:   .00234 lb sec**2/ft**4.

Aubrey Thompson

Exactly what I need. Thanks Aubrey. I'll redo the program.
You obviously teach Physics :)

That gave 12 psi or 342 inches of water at 7500 RPM. Are venturis that effective?

I have Fluid Mechanics by Robert E. Granger Dover I need to re read later today.

Paul Lamar ...No rotor no motor.

The Rotary Engine NewsLetter. Powered by Linux.
ACRE NL web site. http://www.rotaryeng.net
Copyright 1998-2006 All world wide rights reserved.