Velocity diverging error

I am trying to duplicate the Internal Thermal Comfort of a Car| Advanced Tutorial | SimScale . I have done all the settings as it is. But there is a diverging error at Velocity = 1.01783e+07 at position: (1.909 m, 1.075 m, -0.7106 m). I have read the Divergence in Simulation: How to Tell When and Where? | SimScale but am not able to find the issue. Please help me

Hi there,
Thank you for posting on the forum!
Can you please share your project link?
Thank you

I see you have a previous successful simulation run. Can you tell me the difference between both the simulations?

I have added the solar load. Nothing else is changed.

Hello @ndevarakonda , I think the main issue is independent of the solar load since the velocity keeps diverging without radiation and solar loads as well.

An easy fix should be:

-Changing the pressure outlet settings from mean value to a fixed value, this should help stabilizing the solution indeed.
-Increasing the mesh quality, you can refer to the following documentation page for more information.

The former one should solve the velocity diverging problem, and the second one should help improving the accuracy of the simulation as well.

I hope this will be helpful,

Thank you for the response. Which value of the pressure can be given for this? Also I have used a finer mesh before. Even without the solar load, there was error in the simulation. So I have reduced the fineness to 5.5.

I have given the outlet pressure as 101325. It gives an analysis “Found boundary conditions with pressure values which may be invalid: Outlet. For boussinesq simulations please ensure you have specified gauge pressure values at your boundaries.”