Prashanth
Ansys Employee

Yes, it is recommended to use temperature dependent properties with pressure dependent saturation (pt-sat or ptl-sat) or even better, real gas property (RGP) tables with saturation tables.

But using constant properties won't lead to sudden divergence like this. Can you check your y+? Boiling models won't work with low y+ and it is better to maintain y+ greater than 15 or so for stability.