"Thermal Simulation" and "Electronic Cooling Simulation" not corresponding to results of real experiment with same parameters

[d_pflantz]

I performed an experiment consisting of a ‘RH25 DALE 25W 10 Ohm’ resistor to which 5 different powers are induced to see the resulting temperatures. In the published image you can see a diagram with the results of the temperatures expected by calculations, those shown by a temperature measuring camera and the temperatures resulting from the ‘thermal simulation’ and those from the ‘Electronic cooling simulation’.
The results of the simulations do not correspond to those of the physical experiment and I do not understand the (almost) linear path of the simulation results. The maximum temperature reached in the experiment is 169.9°C and for the same power the result of the simulations is 316°C. The margin of error is too big.
Can someone explain to me why the results are so different, considering that the parameters are very similar or the same in the experiment as in the simulations?