How to determine the flow rate of high-pressure air
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I would like to ask the experts: how is the flow rate of high-pressure air determined, for example, for compressed air and nitrogen at 40 MPa?
For the design of the venting calculations, a reference value of 0.7 to 1 times the speed of sound is used, based on the actual venting speed of 0.5–3 m/s
Determining the flow rate of high-pressure air or nitrogen can be done primarily through the following methods: 1. **Using flow meters**: Mass flow meters or volume flow meters can be installed directly to measure the flow rate of air or nitrogen passing through the pipeline. 2. **Application of Bernoulli’s equation**: If the flow within a pipe can be approximated as that of an ideal fluid, Bernoulli’s equation can be used in combination with the measured pressure difference to estimate the flow velocity. 3. **Using a pitot tube**: A pitot tube is an instrument commonly used to measure fluid flow velocity, calculating it by measuring the difference between static pressure and dynamic pressure. For specific cases, it is also necessary to know physical properties such as the fluid density, as well as information on the size and shape of the pipes. Under high-pressure conditions, the compressibility effect also needs to be taken into account. .
Where was this found in which specification?
I don’t know which standard. There is a small Excel tool for fluid calculation on the forum, which includes recommended economic flow rates; these are the data in tables. Regarding the issue of several times the speed of sound, there are posts on the forum about the maximum speed at which safety valves can vent to the atmosphere
Is a gas flow rate of 0.5 a bit low? Also, could you share a link to the Excel sheet for calculating forum traffic speed? We’d like to use it for free: lol
https://bbs.hcbbs.com/forum.php?mod=viewthread&tid=290895 This owner has compiled many calculation software tools