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How do I set a turbulent prandtl number(for example 4.22 instead of the default 0.85,

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Old   June 6, 2015, 21:44
Default How do I set a turbulent prandtl number(for example 4.22 instead of the default 0.85,
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IET
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Dear experts:
In Fluent, the default turbulent prandtl is 0.85 for conventional fluid (air and water et al.), but for heavy metal (lead bismuth eutectic et al.), its turbulent prandtl is larger than 1.0. So I want to set it 4.22 instead of 0.85. But I don't know how to do it? Use UDF?
For standard k-epsilon et al, we can use UDF to change the parameters (as shown in fig. 1). Once you start using UDF, Fluent is at your command.
But if I used is Large Eddy Simulation, not in standard k-epsilon, and there is no TKE Prandtl number. There are Energy Prandtl number and Wall Prandtl number(as shown in fig. 2). In user guide, they are the turbulent Prandtl number for energy and the turbulent Prandtl number at the wall, and the default is 0.85 respectively. If I want to set it 4.22 instead of 0.85, Which one should I modify? If I want to use UDF, How should I do?
Please help me!

1.jpg

2.jpg
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Old   March 8, 2021, 13:57
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Gaurav Kumar
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Facing the same problem.
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