jball1
Mechanical
- Nov 4, 2014
- 79
I am performing an analysis of an event that takes between 0.1 seconds and 1 second. My stable time increment is usually between 2E-7 and 5E-6. In the past, I have used Abaqus Implicit to solve this type of problem. I believe I was told at one point that Implicit methods are generally better for simulating long duration events, since the error accumulates in Explicit due to the much larger number of steps relative to Implicit.
For example, I can usually capture the results that I care about with a time step size of 5E-5. So for a solution I am running out to 0.1 sec, that would be 2,000 time steps in Implicit, and 20,000 time steps in Explicit with a time increment size of 5E-6, and 500,000 time steps in Explicit with a time increment size of 2E-7.
I am curious - has anyone actually found this to be the case? Have you run a simulation for a long duration event and found that the error in the explicit solution builds over time?
Of course, I can run my own studies to compare answers (and I plan to!). But these simulations are pretty expensive, and so if I can benefit here from anyone else's experience, it would be much appreciated!
For example, I can usually capture the results that I care about with a time step size of 5E-5. So for a solution I am running out to 0.1 sec, that would be 2,000 time steps in Implicit, and 20,000 time steps in Explicit with a time increment size of 5E-6, and 500,000 time steps in Explicit with a time increment size of 2E-7.
I am curious - has anyone actually found this to be the case? Have you run a simulation for a long duration event and found that the error in the explicit solution builds over time?
Of course, I can run my own studies to compare answers (and I plan to!). But these simulations are pretty expensive, and so if I can benefit here from anyone else's experience, it would be much appreciated!