Flow/Pressure Formula
Flow/Pressure Formula
(OP)
I am looking for a simple formula to determine the amount of pressure required to cause a certain amount of water to flow through a certain size opening.
To be specific, what pressure is required to make 26.4 GPM of water flow through a .50" opening? Estimated orifice coefficient: .97 Ambient temp: 70 deg F
To be specific, what pressure is required to make 26.4 GPM of water flow through a .50" opening? Estimated orifice coefficient: .97 Ambient temp: 70 deg F





RE: Flow/Pressure Formula
RE: Flow/Pressure Formula
RE: Flow/Pressure Formula
RE: Flow/Pressure Formula
RE: Flow/Pressure Formula
Best equation is that for the orifice application.
Regards
RE: Flow/Pressure Formula
Here are a couple of equations you can use:
dL = sqrt(.0444)(QL / sqrtDP)
where
dL = Diameter of orfice / in.
sqrt = Square root
QL = Required water flow / gpm
DP = P1 - P2 / psi
P1 = Inlet pressure / psi
P2 = Outlet pressure / psi
Additionally, to obtain the Coefficient of Flow (Cv), use the following formula:
Cv = QL / sqrtDP
Another equation to solve for the restriction size for liquid flow follows:
dL = sqrt(QL / .0001423 sqrt(DP / r))
where
dL = Orifice diameter / micrometers
QL = Liquid flow rate / mL / min
r = Liquid density
Some combination of all of those should get you where you need to go.
Hope that helps.
RE: Flow/Pressure Formula
27.216 = gpm ideal
0.061 = cfs ideal
0.001 = sf
44.472 = fps
30.710 = v2/2g
13.294 = delta psi
Remember: The Chinese ideogram for “crisis” is comprised of the characters for “danger” and “opportunity.”
-Steve
RE: Flow/Pressure Formula
Known Values:
Flow: 26.4 gpm
Orifice Dia: .500 in
K Factor: .97
Specific Gravity: 1.00
Results:
13.308 psi at orifice inlet
.05882 ft^3/sec flow
43.137 fps velocity
12.519 psi at orifice outlet