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Old   November 28, 2016, 13:25
Default Natural Convection Air Temperature Problem
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Nils B.
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Hello guys

I am modeling natural convection. Preasure Based and with Boussinesque.

Basicly the simulation is working, but I am not really sure, how to propably display the air temprature.
incoming air Temp : 293.15K
Cylinder Temp: 303.15K
The air closest to the cylinder should have a velocity of 0, BUT not the same temp as the cylinder (physics). When I now display the temperature of the air and cylinder, there is a strange temperature transition close to the wall of the cylinder, that does not seem to be influenced by the air flow velocity. This seems strange to me.

When I now change the Variable to "Wall Adjacent Temperature" All looks quite good to me. But choosing "Wall Adjacent" for free floating air particles does not make mouch sense, does it?

What is the right Variable for displaying the Air temperature in CFD Post?
Is "just" the Air temperature not the actual air temperature?



Hope you can help me!
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Old   November 28, 2016, 14:30
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Kushal Puri
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Quote:
Originally Posted by theBerNii View Post
Hello guys

I am modeling natural convection. Preasure Based and with Boussinesque.

Basicly the simulation is working, but I am not really sure, how to propably display the air temprature.
incoming air Temp : 293.15K
Cylinder Temp: 303.15K
The air closest to the cylinder should have a velocity of 0, BUT not the same temp as the cylinder (physics). When I now display the temperature of the air and cylinder, there is a strange temperature transition close to the wall of the cylinder, that does not seem to be influenced by the air flow velocity. This seems strange to me.

When I now change the Variable to "Wall Adjacent Temperature" All looks quite good to me. But choosing "Wall Adjacent" for free floating air particles does not make mouch sense, does it?

What is the right Variable for displaying the Air temperature in CFD Post?
Is "just" the Air temperature not the actual air temperature?



Hope you can help me!
Picture 2 looks correct. whats the problem in that
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