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dynamic viscosity and the thermal conductivity is constant

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Old   February 11, 2022, 06:10
Default dynamic viscosity and the thermal conductivity is constant
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Hi, there

Recently I am calculating a turbine stage running at subsonic(M=0.8) and transonic(M=1.2) region in CFX. The inlet total temperature is 400K and the inlet total pressure is 4bar. The material is Air Ideal Gas. I just notice that the dynamic viscosity and the thermal conductivity seem to be constant throughout the whole computational domain. May I know if CFX automatically treats the dynamic viscosity and the thermal conductivity as constant?
This treatment seems to be questionable considering the dynamic viscosity is influenced by the temperature via Sutherland’s Law. May I know if Fluent treat the dynamic viscosity and the thermal conductivity as constant as well? How could we define the dynamic viscosity varying with Temperature that can be used in the CFX solver to solve the Governing Equation?

Thank you very much!
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Old   February 11, 2022, 09:16
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It seems you have a setup that you have not reviewed in detail before starting the computation, or reading the documentation.

In the setup, check which material you selected, open the material for it and check the current values and possible options.

You can edit the material and customize it to your liking.

Keep in mind, the setup must be reviewed in detail so you can answer pointed questions from colleagues if need be.
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Old   February 12, 2022, 04:46
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Quote:
Originally Posted by Opaque View Post
It seems you have a setup that you have not reviewed in detail before starting the computation, or reading the documentation.

In the setup, check which material you selected, open the material for it and check the current values and possible options.

You can edit the material and customize it to your liking.

Keep in mind, the setup must be reviewed in detail so you can answer pointed questions from colleagues if need be.
Dear Opaque,
Thank you so much for your always helpful answers! Yes. I've found it in the CFX set-up. I will be more cautious to raise questions next time.
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