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How to justify the internal heat generation in comsol???
Posted 2011年12月29日 GMT-5 03:08 Heat Transfer & Phase Change Version 4.3a 7 Replies
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i am using comsol 4.1. i want to give a internal heat generation on rectangle..how can justify internal heat generation in comsol
any one help me??
thanking you,
parma
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try to add a "HT - right click - Domain Heat Source" to your model (it's in my 4.2a at least ;)
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Good luck
Ivar
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i am using comsol 4.1. i have done one internal heat generation problem. i used Domains heat source menu for internal heat generation. now i want to vary the internal heat generation values. how can vary this value in comsol..it's possible or not....
can you help me???
Thanking you,
parma
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I'm not sure how it was back in 4.1 (everything was not fully implemented) but for HT I suppose its close to my 4.2a, you enter your expression (either with a time variable explicitly or a parameter sweep value to change your heat flux value). In COMSOL almost all fields accept equations, not only constant values
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Good luck
Ivar
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I do need a way to add internal heat and controol the heat release rate and the added total energy?
I.e. turn on internal heat generation at one temperature, controol the reelease rate and turn of when the fuel is consumed.
Is there a way to do this in Comsol?
If not is there any Matlab subroutine to perform such operations.
BR
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have you checed the example of the PID controller, and the thermal control example in the model library (at least there were there for previous versions, if ot check the web site model gallery, this should help you on your way
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Good luck
Ivar
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Thankyou for your answer.
I was though more interested in if there is a way to controol the Q term in the heat transfer equation for solids.
To turn on internal Q at a given temperature, and at a given rate, and turn Q of when a given energy per volyme or per mass has been supplied.
To make this a one time operation to avoid repetition if temperature drops.
Not a phase shift that can be reversed, more like a one time combustion and possible mass loss.
Cp, k, etc. can be made temperature dependant.. But I dont know how to manipulate the mass and Q..
BR
Hans
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by making a new global variale or local field variable and define it (somewhat like the PID controller example)
But you can also give it a sinus or any other function, also periodic, but be sure your BC variation is continuous so the solver might derive a Jacobian
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Good luck
Ivar