Pipeline pressure issue
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I would like to ask about the relationship between the pressure in the main pipeline of a bus-type piping system (similar to a split-cylinder type) and the pressures in the various branch pipelines. Is it true that P_main = N * P_branch (without considering pressure losses in the pipelines)?
The pressures at rest should be equal; it seems that such multiplication isn’t needed in that case either.
The pressure in the branch pipe = the pressure in the main pipe. This post was last edited by QQ Ai on 2009-3-3 18:48.]
According to \"Design of Pressure Piping and Engineering Examples\", the pressure in the main pipe is equal to the pressure in each branch pipe.
The pressures are not equal, as gases have velocity; in other words, there is dynamic pressure. There is a pressure drop from the main pipe to certain points in the branch pipes. It can be said that the pressure in the main pipe is slightly higher than that in the branch pipes, but it’s not the case that P_total = N * P_branch. Only the flow rate follows this relationship: Q_total = N * Q_branch
In terms of design, the pressure in the branch pipe should be equal to that in the main pipe. Although there is a certain pressure drop in the pipeline from the starting point to the ending point!
There is a pressure drop, the flow velocity is changing, and the dynamic head is changing. There is also resistance loss at the same time.