Reply To: TimeStep Reduction in S-ALE

[Ian Do]

Hello Abhemanyu ,

I don't think I can answer this question as to the reason for dt drop.

When the ALE mesh resolution is changed, this affects many things in the computational domain. It could mean the mesh can now pick up high gradients (P, vel, rho, ...) in the flow field, or in the FSI force gradients(?), or advection of smaller chunks of ALE mat (?), etc. dt limits are computed based on many criteria, such as contact, FSI, advection, CFL, mesh size+sound speed, ... Then the smallest dt is used. So you can see that there isn't a clean way to pin down the reason why when dx changes what may happen to dt.  

 

Ian Do