Orifice pressure
Orifice pressure
(OP)
I have a 36" x 72" x 1.75" box with an air input of 100CFM at approximately 70 degrees F. One surface has 2275 0.0625" diameter orifices in it. How do I calculate the pressure at each orifice? The orifice depth is approximately 0.0625".





RE: Orifice pressure
If you can measure the air velocity from the orifice you can calculate air velocity pressure as follows: Pv=C*V^2/2g and the result will have the unit in ft or inches. C is a constant for the orifice and V is air velocity. For static pressure use a manometer.
RE: Orifice pressure
Is there a table that you could point me to for the orifice constant value?
I'm trying to figure out the required CFM of a blower for a specific pressure.
The setup is basically an air-hockey table. I have a known weight for the puck and the minimum number of orifices beneath it at any given time. I need to calculate a blower with enough CFM to float the puck.
RE: Orifice pressure
See: Flow of Fluids Through Valves, Fittings, and Pipe.
Crane Technical Paper No. 410. page 2-14.
Flow of gases and vapors: