adv5_no_dtime

Summary: Stability in transient analyses with a flowrate specified at the exit of the model.

Flag:

Adv5_no_dtime 0

This flag is off by default (value of 0). Changing the Value to 1 enables the flag.

Description

In some transient long running analyses unstable results have been observed at the inlet. The instability typically occurs when a flow rate is defined at the outlet. If this instability is observed at the inlet of a transient using ADV5 (typical setup for a pump), this flag is recommended. The flag modifies the stabilization algorithm regarding advection and diffusion.

The following turbulence models may have limited affects from the flag:

Note: Avoid the turbulence models mentioned if the behavior is observed. Change the turbulence model to SST k-omega and turning on the flag.