thanks for the answer. I would like to simulate the time course of a cooling process.
A temperature load is applied to surface B. The temperature in the center of the surface should also be the source temperature.
The heat sink temperature is constant as you have already assumed.
On the surface A the body is cooled and the temperature is extracted. For this I wanted to create a heat flow with the values from the graph.
The heat flow is actually the output of a heat pipe and the values were determined experimentally.