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Heat transfer setting temperatures not affected by material

So when I do a heat transfer (stationary, 2d), I have a rectangle and I set the top and the sides to 300K, and the bottom to 600K. Then I do temperature profiles of these conditions for two materials with very different thermal coefficients however the temperature profile still look identical. Why does the material have no effect on how the temperature is distributed whereas material has an effect when i use a heat source?

2 Replies Last Post Dec 4, 2013, 6:11 AM EST
Posted: 4 years ago Dec 4, 2013, 3:31 AM EST

So when I do a heat transfer (stationary, 2d), I have a rectangle and I set the top and the sides to 300K, and the bottom to 600K. Then I do temperature profiles of these conditions for two materials with very different thermal coefficients however the temperature profile still look identical. Why does the material have no effect on how the temperature is distributed whereas material has an effect when i use a heat source?


Hi logan,
the thermal conductivity determines the rate with which the heat is transferred by conduction.
If you are doing a stationary analysis I think that is normal that you have identical profiles for 2 different materials, because you are scanning the system at the thermal equilibrium.
You can highlight the effect of the material if you perform a transient study, in this way probably you will see that the 2 materials need different times to reach the same temperature profile.

--
Marino Miccio
Chemical Engineer
www.youtube.com/ScuolaTech
[QUOTE] So when I do a heat transfer (stationary, 2d), I have a rectangle and I set the top and the sides to 300K, and the bottom to 600K. Then I do temperature profiles of these conditions for two materials with very different thermal coefficients however the temperature profile still look identical. Why does the material have no effect on how the temperature is distributed whereas material has an effect when i use a heat source? [/QUOTE] Hi logan, the thermal conductivity determines the rate with which the heat is transferred by conduction. If you are doing a stationary analysis I think that is normal that you have identical profiles for 2 different materials, because you are scanning the system at the thermal equilibrium. You can highlight the effect of the material if you perform a transient study, in this way probably you will see that the 2 materials need different times to reach the same temperature profile. -- Marino Miccio Chemical Engineer www.youtube.com/ScuolaTech

Francesco Carelli
Posted: 4 years ago Dec 4, 2013, 6:11 AM EST
Hi Logan,
The result of the simulation is correct, since you used homogeneous materials, and the same boundary conditions.

It's like in a series of two identical resistors: in the middle the voltage will be the half of the total voltage also with a different couple of resistors if the second couple is formed by identical resistors with a different resistance than the first couple: it changes the current that flows into the resistors, but not the voltage in the middle point of the series.

Hi Logan, The result of the simulation is correct, since you used homogeneous materials, and the same boundary conditions. It's like in a series of two identical resistors: in the middle the voltage will be the half of the total voltage also with a different couple of resistors if the second couple is formed by identical resistors with a different resistance than the first couple: it changes the current that flows into the resistors, but not the voltage in the middle point of the series.

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