Getting Power through a Surface in thermal results

General Questions
1

Is there an easy way for PrePoMax to tell me the power passing through a surface? Currently I am getting it in a convoluted way.

A simple example: a rod of material with one end face set to 300K and the other end face set to 200K. I am interested in the how much wattage is passing through the 300K face. To get it currently, I am doing:
-A Query of flux in the Results tab and select the 300K face. This tells me the “Nodal Sum” flux as well as the Area of the surface.
-Then, on the “FE Model” tab, I create a Node Set and select the surface, which tells me the number of nodes on the surface.
-Next, I multiply the Nodal Sum flux by the Area and divide by the number of nodes; which results in the Watts through that surface

Checking analytically confirms that this approach works and is accurate down to the mW. I feel like there may be an easier way to get this result in PrePoMax, but I could not find it. Side question: Is there a way to get the temperature results displayed in Kelvin?

2

It’s not yet implemented in PrePoMax so you would have to use the Keyword Editor but CalculiX supports so called section print for forces and heat fluxes, among the other. You can find the description in CalculiX’s documentation but you will need something like this:

*SECTION PRINT, SURFACE=surface_name, NAME=section_print_name
FLUX

No, only deg C and F temperature units are supported at the moment. I was going to suggest an option to switch to Kelvins some time ago.

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