Hi Reno. Thanks, it worked. Setting SST and SMT to -1 removed the contact warning and tied successfully the SPH nodes to the adjacent finite elements.

In order to remove artificial waves coming from boundaries in impact modeling, non-reflecting boundary condition (NRBC) is suggested. However, as I've seen so far in my models, NRBC does not work well for SPH nodes except for the fixed SPH nodes. I mean, non-fixed SPH nodes are deactivated when NRBC is applied. Do you have any idea in this regard? Is there anything else playing the same role as NRBC for non-fixed SPH nodes? FYI, I usually fix the bottom SPH nodes, and the side SPH nodes making my target are free. Thanks in advance for sharing your thoughts.