Calculate nitrogen flow rate
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For a DN50 pipe with a nitrogen purging pressure of 5 kilograms, knowing these conditions, is it possible to calculate the nitrogen flow rate? ?
For a DN50 pipe with a nitrogen purging pressure of 5 kilograms, the nitrogen flow rate cannot be determined under these conditions alone. The upstream pressure is 0.5 MPa; an accurate value can be calculated only by knowing the backpressure, pipe length, number of elbows, etc. Flow rate is also related to temperature
It can only be estimated; generally, the flow velocity of gas in pipes is 15-30 m/S. . Assuming 20 m/S, the flow rate is approximately 4 cubic meters per second, calculated as 20X3.14X0.25X0.25. Based on the pressure, it can be converted to a standard gas, and then the mass flow rate can be calculated using the molar mass. . . Good luck. .
I don’t know about the pipe pressure or the end pressure! If you want to know the exact flow rate, you need to use Bernoulli’s equation and determine what conditions are required. Since all the conditions cannot be determined, the flow rate can only be estimated approximately! Take the empirical flow velocity!
If, as stated on the third floor, the gas flow velocity is 15–30 m/s at 0.6 MPa, then what should the flow velocity be at the outlet where the pressure is atmospheric? It basically needs to exceed 100 m/s.
P2/P1>2 means the speed of sound is reached
Everyone: The poster mentioned nitrogen purging, which means the back pressure is at atmospheric pressure; therefore, the flow rate can only be estimated roughly.
It should have reached the speed of sound. If pipeline pressure losses are not taken into account, then all that’s needed is to calculate the density of N2 at 6 kilograms per unit volume, multiply it by the area, and then multiply the result by the speed of sound under those conditions
It is determined by the flow rate of nitrogen and the amount of vaporization
If the Choking state is considered to represent the maximum flow rate that can be achieved, then around 16 tons per hour can be attained; in reality, the value will be slightly lower, but not by much, provided that an adequate amount of nitrogen is available upstream