Jim Day
Ansys Employee
I don't know Abaqus, but I get the impression there are different forms of MPCs. If you want all the nodes to behave as a rigid body, the LS-DYNA keyword is *CONSTRAINED_NODAL_RIGID_BODY (like an RBE2 in Nastran). If you want to retain deformability in the circumference of the pipe, then consider *CONSTRAINED_INTERPOLATION (like an RBE3 in Nastran). The latter would be appropriate in the case where you wanted to distribute load from the center node to the nodes on the circumference.