## General Mechanical

#### Time step

• muneebvohra
Subscriber

Dear Sir
what is the basis for the initial time step formula? and what does it signifies? Can you explain it further?  And what is the maximum or minimum time step? As far as I know, the time step is the difference between two consecutive time intervals. For instance, if the initial time =1s, and the time step is .001 then the system will do analysis at 1.001s. Therefore I am confused about the maximum or minimum time step and how it can impact our analysis?

Thanks

• Wenlong
Ansys Employee

Hi,

I assume you are talking about static or transient structural analysis. The initial, maximum, and minimum time step is referring to the substeps. A step can consist of several substeps, and if you define the initial step, max, and min substep size, your substep will start at the initial value, and varies within the min and max values. This is based on you have turned on "automatic time stepping" and the solver will adjust the substep size to optimize the simulation speed.

This website has a very detailed description of step and substep definitions: https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v193/wb_sim/ds_Steps_Substeps_Eq.html

This website has a guideline for integration step size (in other words, how to choose sub-step size): https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v193/wb_sim/ds_guidelines_int_time.html

Regards,

Wenlong

• muneebvohra
Subscriber

I do not have the account number to sign up. Can you tell me how to get it?

• Wenlong
Ansys Employee