[redneck]

Hello everybody.
I have ferrofluid (water + 4% of Fe3O4 ) multiphase flow through 2D rectangular channel in the presence of a non-uniform magnetic with G=4e-5.
when I change the Under-Relaxation Factor like momentum to 1e-7 with absolute criteria 1e-8, it converge at 300 iterates for example while if i don't change the Under-Relaxation Factor it will stack at 1e-5 and don't converge to 1e-8 with for example 1500 iterates at same mesh.
is that true to change Under-Relaxation Factor and it converge so fast like 300 iterates ? is it something wrong with my work ?
(Im trying to find the best mesh size and converge the problem)

sry for poor English
GL&HF