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Pressure Increase of a Liquid in a Changing Volume (Constant T)

Pressure Increase of a Liquid in a Changing Volume (Constant T)

Pressure Increase of a Liquid in a Changing Volume (Constant T)

(OP)
Hi, I have been looking everywhere for support on a calc I need to do for work. I need to determine the amount of pressure increase that will occur on a constant fluid volume (at a constant temp) when the volume of container it is in gets reduced.
All I have come across in my searching is Boyle's Law, but that is for gases, not liquids. I would assume that the fluid compressibility factor would need to play into this, but I cannot find anything.
Has anyone come across this type of calculation before?

RE: Pressure Increase of a Liquid in a Changing Volume (Constant T)

yep, there was even a discussion on it a couple days ago in this very forum. Try searching down a couple threads.

Patricia Lougheed

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RE: Pressure Increase of a Liquid in a Changing Volume (Constant T)

(OP)
Thanks Patricia, but I could not find anything that was similar to my issue (going back 2+ months). Any more guidance or support on where to find it?

RE: Pressure Increase of a Liquid in a Changing Volume (Constant T)

IRstuff is correct. Based on what you said the only thing you need is the bulk modulus of the liquid. In the real world the modulus of the container is also a factor.

RE: Pressure Increase of a Liquid in a Changing Volume (Constant T)

I apologize, the post I was refering to was actually in a different forum: thread794-327180: Pressure rise due to simultaneous heating of the pipe and blocked-in liquid.. I can't actually open the guy's calculation, wish you luck on that. However, zdas04 gave a response that holds pretty true for real world applications. My response to that individual, and to you as well, is it's generally not a good idea to design liquid systems this way. The pressure goes up rather quickly. That's the reason ASME requires pressure relief valves. I saw the other peoples' responses in forum 794 -- all I can say is that I have seen the results when people scoff and think it's ok to isolate heated liquid-filled pipes. The results are not pretty and can be very expensive, at least in the nuclear field, where the pedigree on that piece of shrapnel that used to be a pipe or a heat exchanger costs way more than you think.

Patricia Lougheed

******

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