Heat Sink Design


I am new to SimScale and I am trying to achieve a thermal solution for my system. My goal is to cool a Power Electronics Board with 6 GaN Switches, each with a power loss of 40W with safety margins included. I have ran a natural convection simulation for the board. The system includes the switches, Inductors, a vapor chamber for a set of three switches, and a heat sink that goes on the vapor chamber, respectively for the simulation.

I worry that the results that I have been getting are incorrect because I feel that there should be a larger heat gradient between the GaN switches and the Heat Sink. My questions is that am I running a natural convection simulation? If so, what are some ways that I may improve my simulation to get more accurate results?

Here is my simulation link: https://www.simscale.com/workbench/?pid=4061368265025402731&rru=b542769e-c7d5-4da2-879f-d7f04ab678bd&ci=6b320c4a-d6b6-4ad5-bb67-c9901ab64929&mt=SIMULATION_RESULT&ct=SOLUTION_FIELD

Hey there, and thanks for using the forum!

I had a look at the simulations and it looks well setup and with a proper mesh.

Can you please elaborate on your arguments to think that the results are incorrect?

The proper way to build confidence in the simulation results is to perform sensitivity or independence analysis, for example:

  • Make sure that you are running enough iterations, checking residuals and convergence of the variables. You can also run for more iterations to see if results change.
  • Make sure that the mesh is fine enough. You can run multiple times with finer mesh each time and see if the results change.
  • See how sensible are your results to the input parameters of the model, such as powers and material properties. Sensitivities should be small with small changes to the parameters.