Discussion Forum

Hello Everyone,

Is there a way to use
* the maximum value of a variable in the subdomain
* the global maximum of a variable in all subdomains
as an expression for a subdomain quantity in Subdomain Settings?

The full problem:
I have a 2D Two-Phase Flow, Laminar, Level Set (chns) model hardly converging. It seems the subdomain quantity gamma plays a special role in this case. If gamma is too small compared to the maximum velocity of the flow, I get "Last time step is not converged." error message. If gamma is too big compared to the maximum velocity of the flow, the convergence is very slow. I cannot really find a good gamma parameter approximately as large as the maximum speed of the flow, as maximum velocity depends on time. For this reason, I would like to use an expression like: max(U_chns) from the last time step as gamma subdomain quantity.

A similar problem is already solved in the Level Set application:
Variable hmax_chns is defined in every subdomain as the maximum of h element size in the specific subdomain. I would like to define a similar Umax_chns variable in every subdomain as the maximum of U_chns velocity. Global maximum (in all subdomains) would be even better.

I appreciate your reply.