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Coupling time dependent heat transer with stationary flow
Posted 19.06.2018, 11:04 GMT-4 Computational Fluid Dynamics (CFD) Version 5.2a 0 Replies
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Hello all,
I want to run a stationary simulation to calculate the turbulent flow in a pipe. Afterwards, I want to simulate the heating up process. So I run a 10 seconds time dependent simulation.
Until here, everything works fine.
My Problem: I Insert a mass flow. When the temperature increases, the density get lower, so the velocity increases.
To reduce the error, I run a second stationary study step, where the velocity is based on the new temperature. But the new velocity is still calculated with the initial density, not with a new one.
Set-up:
Flow: SST, weakly compressible Heat Transer physics Non Isothermal flow Multiphysics
Tried constellations: -Deaktivating the Multiphysics while solving the flow: spf.rho stays constant
Enabling the Multiphysics: While solving the second stationary flow study: Error: Undefined variable. - Variable: CFLCMP
Setting the SST equation from study controlled to stationary: While solving the second flow study: Error: Undefined variable. - Variable: timestept
Disabling the pseudo Time Stepping: Undefined variable. - Variable: timestep
Has someone an idea how to calculate the new flow with the lower density? :-)
Thanks!
Henrik Bode
Hello Henrik Bode
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