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Negative Enthalpy and wrong temperature

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Old   September 3, 2021, 06:05
Default Negative Enthalpy and wrong temperature
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Horst van Gras
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Hi,
I have a persistent problem in openfoam. In the transient part of my simulation I have a negative enthalpy given by thermo.he(). Is this physically possible? I thought the enthalpy should be calculated by h=\int c_p dT. Therefore the local enthalpy in cells should be always positive.
Can somebody tell me where is the source file for calculating the sensible enthalpy in openfoam?



Hence this negative enthalpy I see a drop in temperature below 293K, which for a simple, convection problem should definitely keep above 293.


I'm using second order schemes Gauss linear with a non-orthogonal testgrid. Average orthogonality: 0, max: 1e-6



Thx for any help
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convection, enthalpy, physics, temperature

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