[Techies]

Hi guys,
I'm working on Calculating the difference between inlet pressure and out pressure. I have a problem, my result from auto timescale and physical timescale is not same. Early, I think it is a result from the convergence of the simulation because physical timescale got RMS better. But when i change physical timescale to make RMS same auto timescale case, Pressure is similar to before. I don't understand why. Follow my searches, physical timescale just provide sufficient relaxation of the equation and not affect the result. It means the results is not different.
Has Anyone even work on the physical timescale can explain ?
Thanks a lot