Minimum Time Step

Minimum time step = <float>

Description / Usage

This card sets the value of the minimum allowable time step size in a transient analysis, a useful control if the time step is being decreased due to poor convergence of the transient or iterative algorithm. The input parameter is defined as

<float>

Any floating point number in the same units as specified in the delta_t card.

Examples

A sample card that sets the minimum time step to 1.e-9 follows:

Minimum time step = 1.e-9

Technical Discussion

This specification provides a graceful way for the program to terminate based on the computed time step dropping below the minimum value rather than terminating by a segmentation fault or a divide-by-zero error that could result if the time step becomes too small without the benefit of this control.