User Forum of Software BASEMENT

sajjad

User

Registered: 2014-10-01

Posts: 102

Boundary conditions for local time stepping

Dear forum members,

I have a big model (50000 cells) and in a one part with about 50 cells , I have locally refined the mesh and added about 2000 cells there (50 times local mesh refinement). This considerably slows down the computation. I want to isolate that dense mesh part (artificially, because otherwise it is seamlessly integrated into the model) and create a subdomain. Now, I have two sub-domains : refined mesh small part and rest of the model. I want to use local time stepping to reduce the calculation run time. My question is which boundary conditions should i use to connect the two sub-domains so that the effect of boundary conditions does not or as little as possible affect the solution in the refined mesh sub-domain?

Regards

Stephan Kammerer

Developer

Registered: 2015-03-31

Posts: 67

Re: Boundary conditions for local time stepping

Hi Sajjad,

in my view the only option would be to chose a coupling type 'sequential' to connect both 2D domains. Therefore it should be clear which one is the upstream and which is the downstream subdomain. Chose the option 'two_way_coupling=yes' to ensure that the water surface elevation is handed over to your upstream domain.

Regards Stephan