[Jiricbeng]

Hi,

I am running 2-way FSI simulation and although I read help and a few articles about 2 FSI and ran many test cases, I still cannot see difference between coupling (stagger) iteration and coupling step.

As far as I understood, during coupling (stagger) iteration the data between CFX and Ansys is transfered. So why is there "coupling step"?

To be more detailed, I run steady state FSI to achieve steady state deformed shape of a structure (then I will continue with transient). It is performed on one coupling step. But number of coupling (stagger) iterations is in range 6 -30. I wanted the deformation is performed on the structure and transfered to the CFX. But obviously, during the stagger iteration the data is also transfered from CFX to Ansys and Ansys calculates substeps.
So what is actually difference between coupling steps and coupling (stagger) iterations? Is it just numerics? Because coupling steps shifts the solution in time..

Thanks a lot for clarification!

[Jiricbeng]

Any ideas?