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Pressure pulse generation by the thermal expansion of a film

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Hello, I'm trying to simulate the pressure pulse generated by the termal expansion of a silion structure. In the example the structure is 10 um thick. In order to do so, my idea is to:

1) use the "heat transfer in solid" module for the simulation of the temperature distrubution induced by a heat source (induced by the absorpsion of a radiation) 2) use the "acoustic solid interaction, transient" module for the simulation of the pulse generation and transmission through a fluid surrounding the silicon structure

In solid mechanics ->linear elastic material I added the thermal expansion option and in thermal expansion -> setting -> input model I selected Temperature (ht) in order to feed the temperature distrubution obtained in the "heat transfer in solid" module for the termal expansion.

When I compute the model I obtain meaningless values of pressure (really low) and completely different displacement in the solid if compared to the ones obtained without the acoustic module (i.e. with heat transfer and solid mechanics only). The worst thing is that in the progess window, during the computation, there is no a progression in the time of calculation: it suddendly jumps from the first step to the end. If I choose user defined temperature for the thermal expansion, everything works and the solutor works step by step till the end.

Had someone similar problems? I attached the file with the model Thanks Diego



0 Replies Last Post 2017年12月9日 GMT-5 11:49
COMSOL Moderator

Hello Diego M

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