Air Flow
How to calculate air flow through given opening at a given pressure difference?
Let's say you have a large air-inflated object with an interior pressure of maybe 1 psi. Then you create a 2"x2" opening in that larger air-inflated object. How fast will air (in CFM) escape through that opening if the interior pressure is 1 psi and the exterior pressure is atmospheric. What formula's are used to calculate the air flow? Any help or direction is greatly appreciated...
The simplest (but not necessarily most accurate) method uses energy relations.
Potential energy PE will be converted to kinetic energy KE.
PE per unit volume = P (pressure)
KE per unit mass = v^2/2
KE per unit volume = Dv^2/2 (D is density)
Thus v = sqrt(2P/D)
For the volume rate, multiply v by area of the opening.
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