Air - Orifice coefficient
Air - Orifice coefficient
(OP)
Hello,
In my machine, atmosphere air goes into my vacuum system through some holes.
Trying to apply the following formula, I would like to know where I can find the K coefficient.
h = K * Q2
h: pressure drop
Q: flow
K: Constant flow
The orice is 2 mm diameter, in a 3 mm thikness wall.
Thanks,
In my machine, atmosphere air goes into my vacuum system through some holes.
Trying to apply the following formula, I would like to know where I can find the K coefficient.
h = K * Q2
h: pressure drop
Q: flow
K: Constant flow
The orice is 2 mm diameter, in a 3 mm thikness wall.
Thanks,





RE: Air - Orifice coefficient
http://www.okcc.com/default.htm
Check in the catalogs for specific flow calculations and empirical charts.
Hope that helps.
RE: Air - Orifice coefficient
The information you gave me is good but I am looking for hole flow coefficients at low vacuum pressure:
0 - 0.3 psig
0 - 1 inchH2O
0 - 200 mmH2O
RE: Air - Orifice coefficient
Where:
Cv = Coefficient of flow
Q = Gas flow rate / ft3 / hr
SGx = Specific gravity of gas x
T = Temperature / ?R
P1 = Inlet pressure / psia
P2 = Outlet pressure / psia
SQRT = Square root
I know vacuum calculations seem a little weird, especially first thing in the morning. Just look at it as being 0-200inH2O below whatever your atmospheric pressure is, and the numbers should work out fine.