Gas Headers

[chemeng12345]

When designing a gas distribution header system, does the order at which users are put in the line affect the system? This may be a stupid question... I'm not sure.

I am thinking that because the pressure in the header is controlled upstream of the users, it doesn't matter what flow rate each individual user takes, all users should see the full controlled pressure at their end of the pipe.

Is this correct?

 

[sshep]

If the header is properly sized (with low pressure drop), then the order should not be important. Obviously if the header is undersized then there could be problems with pressure drop having big users at the far end. Conversly, if the big users take-off first then it is possible that the header size may be reduced downstream as the flow requirement decreases.

This reasoning applies to normal plant piping layout and conventional pressure drop calculations, but I am sure people can think of a few specialized cases where velocity and momentum effects could be important to consider with distributing a gas flow.

best wishes,
sshep