I am testing the membrane element of Nx Nastran using SOL 106. I have done a triangle modeled with membrane elements. On the edges of the triangles there are beams. These beams are connected with the membrane through CBUSH elements (only translational dofs). Then I have fixed the vertex of the triangle and constrained the z direction of the edges of the triangles. I applied a normal pressure on the membrane elements. The simulation gone well, but if I do the same model in a plane different than x-y (for example x-z) the simulation does not converge.
Is the membrane elements can be used only in the global x-y plane ?
Hello, membrane elements can be used in any plane .... maybe you want to check if you have adjusted the boundary conditions correctly? You wrote that you constraint the vertex of the triangle in the z-direction. Can you check if these constraints are now in the y-direction when you model the triangle in the x-z-plane? Can you also check if the whole triangle is secured against rigid body motion? Constraining in y-direction only means it could move freely in the x-z-plane which can cause convergence issues.
Martin (Siemens PLM employee)