Cavity based BuoyantSimpleFoam problem where changing temperature causes crashing
 

Hi All,

I am relatively new to Openfoam and am running a cavity based simulation, with a cold and hot wall. The created model has been run through a variation of different temperatures with a maximum working difference of 20K, however when I try to change the cold wall or the hot wall temperatures to increase this 20K value after a certain point the difference in temperature seems to be too high and cases a crash when the simulation is running. I am trying to model transitional flow through the application of different Rayleigh numbers and so need to be able to vary the difference in temperature.

In order to achieve good flow representation at the walls I have used low reynolds wall functions across all of my initial cases as the standard epsilon wall function caused disruptions and circulation patterns at the wall. I don't know why my flow keeps crashing but are there any points that I should check first?

I just don't understand how through changing a temperature value my entire simulation is now not working and will not provide correct outputs, where it previously did at the difference of 20K.



Many Thanks!