Conjugate heat transfer - "Floating point exception" error

Using SimScale Thermal
1

Hello,

I have a question regarding my conjugate heat transfer simulation, name of the simulation is DCDC4 and on the “Run 4” of simulation i got an error saying, “floating point exception”. If u would be so kind to help me resolve this issue and look into my simulation, as maybe i have some additional errors I have missed out on. To explain my project a bit better so that u can understand, I am designing a cooler, to cool 4 DC/DC converters which operate at 700-800W. the idea is to cool them using a heatsink which is above them all and “collects” disipated heat from them, which is then transfered to environment, using 2 fans that ensure air flow over my heatsink.

Thank you very much, best regards.
Filip.

2

Hello Filip,
can you please send us a link to your project for us to have a look at your issue?

Also please make sure that your boundary conditions are defined correctly because mostly the issue lay there.
Best regards
Sebastian

3

I hope this is the link you need, i have enabled support to view my project as well so now u should be able to see it. Let me once again explain the concept I am trying to simulate and what am i looking for from results. I have a printed circuit board which holds 4 DC/DC converters which alltogether generate around 80W per unit max, so around 320 W of heat i need to disipate using a cooler and two fans. I am using simscale to try and determine how large of a heatsink i need, and which fans to go with that heatsink. Heatsink that is currently in my simulation is one candidate, fans would be 40x40mm to 60x60mm maximum size. I am including fans into the simulation throught velocity inlet/outlet boundary condition, maybe that is not the right way. Anyway, error i have encountered was explained in my first message. To sumarize, i need to simulate 4 DC DC converters which each generate 80W of heat, which is throught one aluminum plate and an aluminum heatsink disipated while fans blow throught my cooling station.

Thank you very much, best regards.
Filip

4

Hello Fico,
thanks for sharing your project with us.

One thing you can try to do is to switch one of the velocity boundary conditions to a pressure condition.
This will allow the solver to calculate the inlet or outlet flow based on the flow field instead of the boundary condition, which can help to stabilize the simulation.

Also if you want to implement a fan, please have a look at this tutorial about internal electronics cooling.

Best regards
Sebastian