[mhdali101]

Hi
I have a code for mhd problems which uses navier-stokes and a poisson type electrical potential equation.when i use pressure low pressure convergence criteria (1e-6) pressure loop(Gauss seidal iteration) is converging very fast but going to steady state very slowly and sometimes after some time stepping the residual not changing at all.But when i give very low pressure residual(1e-9) gauss seidal iteration takes a lot of time but reaching steady state fast.Total computation time is less for the later case. what i thought was the opposite.

Any comments on why this happening?


Thanks