Creo Simulate > Reference Links > Percent Convergence
  
Percent Convergence
If you selected Multi-Pass Adaptive for the convergence method, you enter a percentage to determine the accuracy level. The percentage applies to the convergence quantities you select.
During the analysis, Creo Simulate performs calculations at increasingly higher polynomial orders for each element edge. An analysis converges when the difference in the results of the last two calculations is within the percentage you specify here.
You should enter a value between 1% and 25%. Lower convergence percentages yield more accurate results, but Creo Simulate may take longer to reach convergence.
You should balance the level of accuracy you need with the amount of time the analysis will take to run.
If an analysis does not reach convergence during a design study, the results may not have the desired accuracy. In this case, you need to change something in your model to get better results.