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Time Scaling Coeffecient for Transient Analysis- Heat Transfer Model

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I am trying to do Heat transfer Analysis using the Conduction Application Mode and it is going to be aTransient Analysis- currently using version 3.5.
My question is regarding the time-scaling coeffecient, Dts_T. If I want to supply a 10 micro second heat pulse (Q), would I just put in 1E-5 as the user defined value for Dts_T.

To rephrase: I would want to supply heat pulse (Q) for 10 micro seconds and observe the temperature rise in the device during this period of time.

Also is there a way to increase the step size: right now Comsol is doing a 1.02E-14 step size. This could possibly take a very long time.

Thank you!
Ayan

2 Replies Last Post 1 mar 2012, 14:10 GMT-5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 29 feb 2012, 17:35 GMT-5
Hi

It's too long since I used 3.5 now, but I do remember there where a place to adapt the time stepping from automatic/free to intermediate or strict, try check the doc.

One thing with short pules and HT in transient be sure you mesh is fine enough to resolve the gradients normally h<sqrt(alpha*Dt) where alpha=k/rho/Cp the heat diffusion and Dt the time stepping, while h is the average mesh size

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Good luck
Ivar
Hi It's too long since I used 3.5 now, but I do remember there where a place to adapt the time stepping from automatic/free to intermediate or strict, try check the doc. One thing with short pules and HT in transient be sure you mesh is fine enough to resolve the gradients normally h

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Posted: 1 decade ago 1 mar 2012, 14:10 GMT-5
Dear Ivar,
I did find out the Stepping Range and will try that out. Thanks for the help. Appreciate it.

Best,
Ayan
Dear Ivar, I did find out the Stepping Range and will try that out. Thanks for the help. Appreciate it. Best, Ayan

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