i tried a very simple model of "electric current" + "Heat transfer" in an argon medium, i added the "Equilibrium Discharge Heat source" to get the joule heating in the gas, the model boundaries are all defined and electric current density is applied at a small area represent the cathode tip and the ground is at another side to represent the anode, the time dependent study works without a problem, however just changing the study to stationary, the model just never converges with many meshes and the temperature blow up to 10s of billions at the very few iterations/steps. this only happen if i add the Equilibrium Discharge Heat source, without it the model converges perfectly. is there any solver modifications that can lead to a good stability of the solution, this is not a time dependent problem, and many authores solve it easily with the stationary methodes.
Thanks