Does the Adiabatic Gas Equation Apply to Liquid Compression at High Pressures?

AI Thread Summary
The discussion focuses on calculating the temperature rise in a liquid subjected to high pressure (7000 bar). The original poster questions the applicability of the adiabatic gas equations for this scenario, noting that most liquids are incompressible and expressing doubt about using gas equations for liquid behavior. They acknowledge the complexity of thermodynamics and seek guidance on determining the temperature rise. A suggestion is made to start with the pressure-volume equation for liquids, incorporating the bulk modulus to calculate compressional work, which relates to temperature change. The conversation emphasizes the need for a suitable approach to model liquid behavior under extreme pressure conditions.
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Hi all,
Hope you can help I am trying to figure out the temperature rise in a liquid subject to high pressures (7000bar in this case)

Is the below adiabatic gas equation still suitable? or is there another way of working this out for liquids?

T2 = T1(v1/v2)^y-1
P2 = P1(v1/v2)^y
Were y = Cp/Cv

I tried working this out backwards from the theory that pressure = f/a = energy/volume but i got a bit lost along the way lol
 
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Most liquids are essentially incompressible, so I wouldn't expect a great rise in temperature. And I wouldn't think that using gas equations to model liquid behavior would be accurate, either.
 
unfortunately nearly incompressible doesn't count at 7000 bar, i don't expect the rise to be to great but i need to figure out what it will be and don't know enough about thermodynamics to get there!
I did stumble across the answer on a different forum a few months ago but I am damned if i can find it now!
 
Try starting out with the pressure-volume equation for a liquid: V=V0e-βP where β is the bulk modulus, and V0 is the volume at low pressure. Use this to calculate the compressional work done. That should be equal to CpΔT.
 
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