Different time steps and bisections for solving same subcase of a problem

In certain cases, users may encounter varying time steps and bisections when solving the same subcase of a problem. This variation can lead to doubts about the accuracy of the results. However, there is no cause for suspicion, as the results are indeed accurate.

Some reasons are:

• It has been seen with some cases that solver in first inspection do not shows any indication of badly conditioned matrices. But solving a matrix sometimes led to ill-conditioned tangent matrices in resolution phase.
• Numerical simulation results turn out to be unstable, since they depend on the machine precision.
• This may happen due to machine precision if we are comparing in two different machines.
• Presence of friction contact in simulation have also reported such instances, but actually friction presence required a non-symmetric solver