Hello,

I just want to discuss a few things about the non-reflecting boundary condition (NRBC) function in LS-DYNA. In fact, I am studying a fluid-structure interaction problem using LS-DYNA Finite element explicit code. My main interest is to study the propagation of shock wave as well as its interaction with the structure. So, I modelled the fluid part using solid acoustic elements (along with *MAT_ACOUSTIC) in LS-DYNA. Then, I applied the pressure to the fluid elements. But, the problem is that I cannot introduce both loading and boundary conditions (NRBC) on the same segment at the same time. It happened that the non-reflecting boundary condition that I introduced does not seem to be working.

So, I would like to know if there is any way to activate the non-reflecting boundary at a later time step different from the load application time (preferably at the end of my loading phase).

Thank you very much.

Regards

Ye Pyae Sone Oo