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-   -   Pressure does not increase in heated enclosed domain. (https://www.cfd-online.com/Forums/openfoam-solving/243598-pressure-does-not-increase-heated-enclosed-domain.html)

Yupp June 27, 2022 08:37

Pressure does not increase in heated enclosed domain.
 
Hello everyone.

I hope this is the good thread, I'm brand new to this forum. I'm new to openfoam and trying several solvers (excuse my bad English). Right now I'm trying to use interCondensatingEvaporatingFoam. This is my problem: I want to compute the thermodynamics of water in an enclosed area. Initially, a 2D rectangle is fullfilled with liquid water at 20 °C. All the boundaries are walls. The walls heat the water until phase change occurs and until the domain is fully gaseous water.

My problem is huge and I think I made a huge error in reasoning that I can't see: pressure does not really increase (a few hPa) during the whole process.
I'm pretty sure I've made an enormous error, but I wanted to have your opinion on the source of it.

These are the conditions:
- Initially motionless liquid water inside the enclosed domain, 20 °C and 101325 Pa.
- The walls are at 120 °C.

According to the liquid equation of state, the saturation temperature is considered to be constant at 100 °C. The liquid water reaches 100°C, then changes phase, and then the gas thus formed reach approximately 120 °C inside the domain. Turbulence is took into account (k-w SST), the mesh seems correct regarding
the y+ and the temperature gradients. The transport properties of the liquid/gas seems correct. I really do not understand. As the problem is at constant volume, considering the conservation of mass, the pressure should experience a huge jump during the phase change and then during the heating of the gas thus formed.

Does someone have an idea ? Is it the solver that is not suitable for this problem? Are my conditions bad? Am I misunderstanding the physics of the problem? Do not hesitate to ask me to display the files which could be the source of the error.

I can show you the files, but since I don't know the source of my problem, I don't even know which ones to show you. Do not hesitate to ask me to display the files which could be the source of the error.

Thank you foamers.


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