Okay, so I just ran two topology optimisation simulations for the exact same part (one after the other), the only difference was the Factor of Safety. My first one I selected a factor of safety of 8 and the other of 5. The FS 8 ran for about 60 iterations before converging while the FS 5 ran for 80 but failed to converge so I'm 100% sure my load cases are correct. I looked at the .out file and the FS 5 got to the 2nd convergence criteria a few times, each time it would come up with warnings that the loads epsilon values are larger than 10% after that 2nd criteria is met and then it would iterate another 20 times before it says 1st and 2nd criterion met until 80 iterations are completed.
The 1st convergence criteria also doesn't seem to start when it should.
For example, in the FS 5 case: topoOpt.out (FS 5) iterations 67 through 75.
The convergence criteria seems to change between iterations. Sometimes it will say that a percentage change of 0.37% is enough to satisfy the 1st convergence criteria like (iteration 54) or 0.28% is enough to satisfy the 1st convergence criteria like in (iteration 64) but then 0.19% change like (iteration 67) or 0.31% (iteration 68) or 0.22% (iteration 70) doesn't satisfy the 1st criteria.
Any help would be appreciated.