Inrease in water pressure as a function of temperature under constant volume

AI Thread Summary
The discussion focuses on calculating the increase in pressure within a closed pipe network as water temperature rises from 25°C to 55°C. Participants emphasize the use of steam tables, which include data for compressed liquid water, to determine the pressure change. The first law of thermodynamics is referenced, indicating that all internal energy changes result from heat transfer, with no work being done. There is a consensus that steam tables are necessary for solving this problem, despite some confusion about their nomenclature. Overall, the method involves calculating heat transfer and then consulting steam tables to find the corresponding pressure.
ageorgakis
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Hi all. I have a large pipe network that can hold say 1000 cubic meters of water. The pipe network is closed and pressurized to say 10 barg at 25 deg C. If the temperature of the water increases to 55 deg C, how much will the pressure in the pipe network increase?

I would appreciate if you could point out the method of solving the problem including tables and formulas.

Thanks.
 
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This ia a job for steam tables and the first law of thermo and possibly a H-S chart.
 
The water is between 25 to 55 degC so I don't think the steam tables or the thermo laws will do any good. This is a pressure vs temp vs volume problem. if it was a gas then a simple ideal gas law would work.
 
ageorgakis said:
The water is between 25 to 55 degC so I don't think the steam tables or the thermo laws will do any good. This is a pressure vs temp vs volume problem. if it was a gas then a simple ideal gas law would work.

Steam tables, in an odd use of the nomenclature, include compressed liquid water. No idea why they are still called steam tables but they are.

You came and asked the question as to how to solve is. I've told you. It's water, therefore you use the steam tables, there is no debate about that. You find the heat transferred to the water (using the mass and specific heat capacity). As no work is being done (from the first law) we know that all internal energy comes from transferred heat. You can then look up from a steam table the pressure.

I've not used steam tables or done anything with thermodynamics of fluids in quite a while (since uni in fact), I can't remember exactly what you have to do i'll have to read up for that.
 
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xxChrisxx said:
Steam tables, in an odd use of the nomenclature, include compressed liquid water. No idea why they are still called steam tables but they are.

You came and asked the question as to how to solve is. I've told you. It's water, therefore you use the steam tables, there is no debate about that. You find the heat transferred to the water (using the mass and specific heat capacity). As no work is being done (from the first law) we know that all internal energy comes from transferred heat. You can then look up from a steam table the pressure.

I've not used steam tables or done anything with thermodynamics of fluids in quite a while (since uni in fact), I can't remember exactly what you have to do i'll have to read up for that.

It's been such a long time since uni I can barely remember any of this. I wish I had my old books. I'm doing some research on the net but it isn't easy.
 
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