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Defining a time dependent heat source (Heat transfer)
Posted Feb 2, 2024, 4:19 p.m. EST Heat Transfer, Mesh, Equation-Based Modeling Version 6.0 3 Replies
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Hey there,
I am solving a heat transfer problem in which there is a time dependent heat source for a particular domain in the geometry. The heat source to be implemented is:
(1) If the temperature of the element (mesh element of the mesh corresponding to the heat source domain) is below a certain temperature "To", heat source = f(t), where t is the time. (2) If the temperature of the element crosses To, heat source = f(t, to), where to is the time at which the temperature of the element crosses To.
So to define this type of a heat source, I need to know the temperature of each mesh element, the time at which the temperature of the element becomes To.
Would be a great help if anyone can let me know how can I impelement such a heat source function.
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My guess is that OP doesn't really need to work with individual mesh elements. Most always it is enough to define a volumetric heat source that is a function of local temperature. Without more details I don't immediately see how to implement the dependence on the time the temperature crosses a threshold, although I suspect state variables might be a way to do handle this.
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Hi,
I understand that you want to determine the time for each location when a certain temperature threshold is reached. You need to implement an additional equation for this. This blog post by Walter Frei may help: https://www.comsol.com/blogs/using-the-previous-solution-operator-in-transient-modeling/
Cheers
Edgar
-------------------Edgar J. Kaiser
emPhys Physical Technology
www.emphys.com
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Hello Dave and Edgar,
I was able to fix the issue by using state variables and some conditional statements. The blog on using the previous solution operator was useful too.
Thank you!