SimScale CAE Forum

Calculate Total Heat Load?


Is there a way to calculate the full heat load on the entire model after solving? (in Watts) It’s always nice to do a double check after the solve, just to make sure…

I tried looking in the output file, but I did not see it. Also, I don’t know French. :slight_smile:

Also, quick request - It would be AWESOME if we were able to just input the volumetric heat load in Watts (just have Simscale calculate the W/m^3.)


@rszoeke/@ahmedhussain18 is this possible?


Hi @fastwayjim,
currently this is not possible on the platform since we would need a result control item that can do an integration operation (besides min/max, nodal average and sum) and a dot product with the surface normals. We could either provide a general integration option for fields. This would be a general tool for integrating variables over a surface, but with this you would only get correct results for plane surfaces. On the other hand we could add a specific total surface flux result control which would specifically compute the total normal heat flux through the assigned surfaces. Which one would you prefer? Would the general approach with the simple field integration be enough?

For the time being this could also be achieved with a chain of filters in paraview:

  • (optional) use extract blocks such that you can restrict the computation to specific volumes or faces
  • extract surface
  • surface flux (it essentially does compute the dot product Normals.heat_flux and integrates over the surface)

You should get a variable Surface Flow which shows the total heatflux through the specified block’s surface.



It comes down to giving the user the confidence that they have set up the thermal model using the correct amount of power. More often than not, this value is known as watts (for electronics, this is an output of an electrical power analysis done by the Electrical Engineers).

The current workflow involves extracting the volume from CAD, and putting that in a spreadsheet along with the power (output from the EE), and calculate the Watt/m^3. This introduces an extra step, with the potential for human error.

If you can’t provide an output easily, then can we at least allow the user to just input a “body heat load” in Watts?


Hi @fastwayjim,
now I understand the actual problem.

this would be definitely possible. I’ll add this feature request. If accepted it shouldn’t take much to implement it.



Awesome, thanks! In general, I think anytime there is an opportunity to “remove another calculator” (i.e. omit the use of excel during pre-processing), we should take advantage of it!


Couldn’t agree more! Initial condition values for turbulent quantities (k, Omega) is another example for that! We working on moving more and more of these calculations into SimScale!