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turbulent energy dissipation rate

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Old   February 23, 2023, 10:20
Default turbulent energy dissipation rate
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Hello,


i have a hopefully simple question for using UDF.
I try to implement a new coalescence kernel for PBM.
This contains the turbulent energy dissipation rate epsilon.
I am using:


eps = C_D(cell, tm);


turbulence model is RNG k-epsilon.


I get a SIGSEGV
The fl process could not be started.


I know its about epsilon because error does not occur when using eps = const.
what do i have to consider? Do i have to save epsilon?

Thank you.
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Old   February 24, 2023, 05:05
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Update:


As i told I am using RNG k-epsilon model, where epsilon should be saved.
What i did not considered is the "dispersed" option, which is only calculating epsilon for primary liquid phase.



So I changed my code in Aggregation kernel into:


epsi = C_D(cell, tp)
with:
*/ Thread *tp as primary liquid phase */



Additional information: Theory Guide uses epsilon(liquid phase) for prince&blanch aggregation kernel for bubbles as well.


No error occurs!

Does anyone know if this approach is valid?


thanks
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