Hi,
I have found that whenever "Time dependent" option is turned on, which according to help:
Select the Time dependent check box if your problem is transient (i.e., unsteady), and specify the analysis physical time in the Total analysis time box, the time step of results outputs in the Output time step box.
After completing the Wizard, you can modify these settings in the Calculation Control Options dialog box.
The calculation becomes much slower. Without this option, a simulation converges typically in less than 200 cycles, and the Solver's Info window does not display the real "physical time", but merely CPU time; When this option is on, what previously takes two minutes could increase up to like ten minutes.
What is the nature of turning on "Time dependent" option? if it is merely to prevent prematurely stopping the simulation, then it is merely a "non-stop" option. But from the significantly lowered simulation speed it seems that something else is also happening. What is happening behind the hood with this option?
Jerry
hi jerry, if you want to understand the nitty gritty of the calculations, check the technical reference and solidworks simulation kb.
but from a more practical perspective, this is a fundamental selection for your analysis similar to internal vs external. do you want a steady state solution or do you want a time dependent solution? ie, the results after a long period of time when the system settles or over time. there are very few problems where you need a time dependent solution for something that will be come steady state (take a look at the cylinder flow tutorial).
why does it take longer? because it isn't iterating to a solution, it is calculating every individual time step. you're working in real time, not just iterations. for some phenomena, the time step needs to be very small, which can lead to a long solve time. have al ot of cells? even longer. setup and run a steady state solution to get an idea of how the system will work before going to tiem dependent.