relaxation factor

Hi experts,

I am having trouble with the covergence in the acusolve simulation. I read about the relaxation factor and tried with few values and here are the results. I am seeking for your comments about which result is good in terms of stability. Also, I am looking some suggestions about convergence just by looking at these plots. (All the simulations are equivalent to each other except the relaxation factor).

The first image (rf = 0.1) seems to be stable but the solution ratio is not changing at all, which means it may not have converged.

I want to avoid wiggles that I see in the second image (rf = 0.6). 

May be the third image is good. I may need to decrease the convergence tolerance (rf = 0.8). Also note that this simulation has converged at time step ~66.

Thanks.