Please help The flow rate required to yield a specified reading on an orifice me
ID: 792999 • Letter: P
Question
Please help
The flow rate required to yield a specified reading on an orifice meter varies inversely as the square root of the fluid density:
V2(cm^3/s)=V1(cm^3/s)(Density1/Density2)^(1/2)
a) Suppose an orifice meter calibrated with nitrgoen at 25 degrees celcius and 758 mmhg is used to measure the flow rate of a process stream of hydrogen at 50 degrees celcius and 1800 mmhg, and the value read from the calibration chart is 350 cm^3/s. Calculate the true volumetric flow rate of the gas.
b) Repeat part (a), only suppose the process fulid contains 25 mole % CH4 and the balance C3H8.
Explanation / Answer
Formulas:
? = m/V
Pfluid
= ?gh
Ptotal
= ?gh +P0
= PG
+PA
F2
= F1
(A2
/A1
)
B = wfluid
Q = ?V/?t =Av (Flow rate)
?1
A1
v1
= ?2
A2
v2
P1
+ (1/2)?v1
2
+ ?gy1
= P2
+ (1/2)?v2
2
+ ?gy2
F =?Av/l
Main Ideas:
1. Definition
2. Pressure