I Kappa factor in heat equation and heat Flux

AI Thread Summary
The discussion centers on a simulation project involving two concentric cylinders with an insulating material, aiming to analyze spatial and heat flux evolution. The user observes that changing the kappa value of the insulator does not affect the heat flux, despite variations in temperature. The equation j_q = -k(r)∇·T is referenced, indicating the relationship between thermal conductivity and temperature gradient. Participants suggest documenting the analysis in detail to clarify the observed phenomenon. The issue highlights a potential misunderstanding of how kappa influences heat flux in the context of the heat equation.
George444fg
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I am doing a project, actually it is a simulation. And we aim to determine the spatial and heat flux evolution of the system. The system consists of two concentric cylinders separated by an insulating material. I change the value of kappa of the insulator but the heat flux remains always the same, despite the change in the evolution of the temperature. Why this is happening?
 
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George444fg said:
I am doing a project, actually it is a simulation. And we aim to determine the spatial and heat flux evolution of the system. The system consists of two concentric cylinders separated by an insulating material. I change the value of kappa of the insulator but the heat flux remains always the same, despite the change in the evolution of the temperature. Why this is happening?
What exactly is kappa, and what, more precisely, is the particular problem you are trying to solve? Also, documenting some of your analysis might be helpful.
 
I mean it is the equation j_q=-k(r)\nabla \cdot T. I use the heat equation. The point being that no matter the values kappa gets the heat flux is always the same
 
George444fg said:
I mean it is the equation j_q=-k(r)\nabla \cdot T. I use the heat equation. The point being that no matter the values kappa gets the heat flux is always the same
Like I said, let's see what you did in detail.
 

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