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Using a stationary solution for time-dependent problem

Posted Mar 20, 2019, 6:51 a.m. EDT General, Computational Fluid Dynamics (CFD), Chemical Reaction Engineering Version 5.4 3 Replies

Till Henrich
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Hello,

I have solved a stationary model for a flow field and temperature distribution.

In the next step I want to solve a time-dependent problem for mass transport. In the inlet there's a change from substance A to substance B. The substances are completly the same in their physical properties, the only thing that changes is its name. It's for calculating a residence time distribution.

So my question is: Is it possible to solve only for the time-dependent mass transport, without solving for the flow field and temperature, because they a same as in the stationary solution? I think this should reduce the amount of time required for the solution....

Thanks in advance! Till

3 Replies Last Post Mar 25, 2019, 5:12 a.m. EDT
Marvin Tiemessen
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Posted: 6 years ago Mar 21, 2019, 10:16 a.m. EDT

I never did this, but in study steps, you can choose to simulate certain physics; e.g. only calculate the heat transfer module, or in your case, calculate for the mass transport case.

You should use the solution of the steady-state as an initial condition for the flow and temperature field to make this work.

Good luck and hope this helped.

-Marvin

I never did this, but in study steps, you can choose to simulate certain physics; e.g. only calculate the heat transfer module, or in your case, calculate for the mass transport case. You should use the solution of the steady-state as an initial condition for the flow and temperature field to make this work. Good luck and hope this helped. -Marvin
Lasse Murtomäki
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Posted: 6 years ago Mar 25, 2019, 4:04 a.m. EDT

I use steady-state flow field in the time dependent mass transfer problem. First, calculate only the fluid dynamics at steady-state. Then use it as the convection term in the Transport of Diluted Species node by selecting the velocity field "spf". Activate only "spf" node at steady-state and "tds" in time dependent study.

BR Lasse

I use steady-state flow field in the time dependent mass transfer problem. First, calculate only the fluid dynamics at steady-state. Then use it as the convection term in the Transport of Diluted Species node by selecting the velocity field "spf". Activate only "spf" node at steady-state and "tds" in time dependent study. BR Lasse
Till Henrich
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Posted: 6 years ago Mar 25, 2019, 5:12 a.m. EDT

Thank you!

I'll try it...

Thank you! I'll try it...

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