Abdullah Hassan
Bbp_participant

Thank you. 
Now how can I investigate that what is the problem.
If I see the residuals or heat flux values as heff = Q/Tref-Twall then both are showing normal trend i.e. there are no spikes or abnormality or noise.

I have also tried to reduce the time step size from 0.0008 to 0.0006s so that if there is some problem arising due to timestep, it should be resolved but the problem persists.