When looking at the output file of my solver, I have been told that the time-step taken by the solver depends on parameters like the total number of elements and their relative size in my geometry, or the material properties. A material with a high Young modulus could decrease the time step taken by the solver, as well as high number of elements, or elements with great difference in size. I am solving under explicit solver.
More specifically, the time step appears to be the time needed for the information to go through one element to another.
This gets me quite confused. How is time step related with these parameters ? Is there any formal physical relationship ? What about this time to go through an element, does it have mathematical foundation? Is there any advice to get it fit correctly ?
Edit: I am running a time-dependent linear elastic simulation in solid mechanics indeed.