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Magnetic field and Thermal study Combined
Posted 2018年5月21日 GMT-4 10:46 Low-Frequency Electromagnetics, Heat Transfer & Phase Change Version 5.3a 5 Replies
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Hi,
I am currently simulating a model (magentic field study) to evaluate the heat source distribution surrounding an copper inductor cavity and wanted to consider these heat sources asinput for my thermal model .
There is no problem in magnetic field study , can see the surface loss density plot (mf.Qsrh) but when i assign this mf.Qsrh value in thermal model as assigned heat flux I am getting some errors while comuting thermal study ,
- I can see same intial temperature at all time steps
- If not the above error (1) , getting error as undefined variable on boundaries (boundaries where heat flux is assigned)
I am attaching my model here , kindly let me know what is the nature of this error.
P.S - I have also included a PID study in this , however dont feel PID is reason for this error . Correct me if I am wrong
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Hi,
I have downloaded your attachments, and there are some confusing problems. It seems that materials "1.2343 thermique" and "1.2343 inductif" are related to the temperature for the density is Rho(T) and the same as Thermal Conductivity and Constant pressure heat capacity. However, I did not find the function expression, and it seems that you did not set temperature as input variable in the temperature-related meterials. I hope this will help you
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Hi,
I have downloaded your attachments, and there are some confusing problems. It seems that materials "1.2343 thermique" and "1.2343 inductif" are related to the temperature for the density is Rho(T) and the same as Thermal Conductivity and Constant pressure heat capacity. However, I did not find the function expression, and it seems that you did not set temperature as input variable in the temperature-related meterials. I hope this will help you
oh, I found the function expression of Rho(T), but you did not set the unit
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Hi,
I did check the material definitions and everything seems to be fine. Inorder to check the source of error, i tried to run simulation without magnetic field study (performed only thermal study with some assumptions on heat sources) then thermal study runs fine . I feel the problem exist only when both magnetic field study is combined with thermal study and heat flux is unable to read the term mf.Qsrh. I have done similar kind of study earlier but never found such errors , not sure if this source of error comes from design aspect.
I am attaching the screenshot of error which i get whenever i tried to compute thermal study. The boundaries which are showing errors are ones where heat flux is being assigned (with inputs from magnetic field study mf.Qsrh).
Attachments:
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Hello,
What study are you using ? COMSOL might not be able to evaluate mf.Qsrh in a stationnary study (usually used for heat transfer model, so I am assuming you used that). You may need to do a frequency analysis of the mf study and then, in a second step, a stationnary one.
Hope it works !
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Also, I don't think mf.Qsrh is a Heat Flux. q is the heat flux of a model but Q usually refers to a Heat Source. Therefore, when setting up your physics, do not use the "Heat Flux" boundary condition but the "Boundary Heat Source" condition. (By right clicking on the physic node).