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Total power dissipation density value is different across studies

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Hi,

I have been performing some simulations in COMSOL using a cube 0.20.20.2 m^3. First I performed a frequency domain study (frequency: 200 kHz, electric currents module) by setting +10V at one side of the cube and -10 V at the opposite side of it and extracted the total power dissipation density value (using "ec.Qh") from there. From the results I obtained I concluded that this is the RMS value and not the amplitude. Next, I used that value on a time-transient heat problem (module: heat transfer in solids. I also selected the electric solution in "values not solved for") as a heat source. However, when I plotted the variable "ec.Qh" to obtain the total power dissipation density using the solution from the heat study as the data set I got the amplitude value instead of the RMS value.

Any hint on why does COMSOL does not use the same value for "ec.Qh" for both studies? It seems to me that the RMS value is the correct value to be used and I can relate the amplitude and the RMS values easily, but I would like to know more about this issue. The .mph file: https://drive.google.com/drive/folders/1QW7h4oXKG-poaOytwMTdgjMFGPzGZC_q?usp=sharing

Thanks in advance. Regards, Nichal


0 Replies Last Post 10 avr. 2018, 11:46 UTC−4
COMSOL Moderator

Hello Nichal Gentilal

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