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Thermal Simulation Question

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I'm trying to model the conductive heat transfer between a heated wire and the rest of my device. The problem is, when I apply a temperature boundary condition to the wire, it doesn't seem to conductively transfer to other parts of the model. I tried adding the "thermal contact" boundary condition, but it doens't seem to allow me to select any boundary of my model (it states "not available" for each boundary).

I'm LiveLinking the part from Solidworks if this makes any difference. I've attached the photo of my output for reference. Thank you so much in advance for any help you have to offer!



1 Reply Last Post Jan 4, 2021, 4:42 p.m. EST
Robert Koslover Certified Consultant

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Posted: 4 years ago Jan 4, 2021, 4:42 p.m. EST

Well, if I was modeling the transfer of heat from a heated wire to some environment around it, I probably wouldn't try to constrain the temperature on the wire surface, since I doubt that I would know its exact surface temperature distribution in advance. Rather, I would model the sources of heat (ohmic losses due to an electric current, perhaps?) in the wire and account for the thermal properties of the wire (thermal conductivity and specific heat) and surrounding environment. I'd probably constrain the outermost computational boundary to some fixed temperature (like a room temperature), although other boundary conditions might possibly apply there. In a time-domain model, I would define the temperature everywhere, starting at time t=0, and define and apply a time-domain excitation (source of heat), and let the problem advance in time for small enough time steps to model the details adequately, and for as long a time as I needed for my application. In a steady-state (equilibrium) model, I wouldn't need initial volume temperature conditions, just all the right boundary conditions, and a source of heat. Ok, so if those comments don't help you figure out what to do, I suggest you post your model to the forum. You might also want to study some of the thermal models already provided by Comsol, in the Applications Library. Good luck.

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Well, if I was modeling the transfer of heat from a heated wire to some environment around it, I probably wouldn't try to constrain the temperature on the wire surface, since I doubt that I would know its exact surface temperature distribution in advance. Rather, I would model the sources of heat (ohmic losses due to an electric current, perhaps?) in the wire and account for the thermal properties of the wire (thermal conductivity and specific heat) and surrounding environment. I'd probably constrain the outermost computational boundary to some fixed temperature (like a room temperature), although other boundary conditions might possibly apply there. In a time-domain model, I would define the temperature everywhere, starting at time t=0, and define and apply a time-domain excitation (source of heat), and let the problem advance in time for small enough time steps to model the details adequately, and for as long a time as I needed for my application. In a steady-state (equilibrium) model, I wouldn't need initial volume temperature conditions, just all the right boundary conditions, and a source of heat. Ok, so if those comments don't help you figure out what to do, I suggest you post your model to the forum. You might also want to study some of the thermal models already provided by Comsol, in the Applications Library. Good luck.

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