NX non linear material FEM/Sim Problem
NX non linear material FEM/Sim Problem
(OP)
thread825-202613: NX Nastran Contact analysis
I used the above thread as initial information because I am doing a non linear material FEM.
Currently we are investigating the ability to model organics and thus are using Ogden and Mooney-Rivlin Materials.
My problem is exactly the same as the one referenced above. I can apply a Fixed Constraint to one face of a 2x2x2 inch cube. The cube is meshed using Tet(10) elements and therefore is a 3D solid body. I apply a pressure to the opposite face and get the error as follows.
"NASTRAN Msg: ***WARNING: No element connection for node 1 directions 4, 5, 6
***WARNING: Similar warning suppressed for 313 other nodes.
NASTRAN Msg: ***WARNING: Nodal degrees of freedom without element
connection have been fixed for data input file.
This is a very confusing error message to me. When I mesh the box as a solid body, how are the elements not connected in some way ? The simulation will work if I apply two Enforced Displacement Constraints(the only displacements are in the X and -X directions with all others zero'ed) to the opposite faces but gives me an error when i attempt to Fix on face and load the other.
Any help is appreciated !
I used the above thread as initial information because I am doing a non linear material FEM.
Currently we are investigating the ability to model organics and thus are using Ogden and Mooney-Rivlin Materials.
My problem is exactly the same as the one referenced above. I can apply a Fixed Constraint to one face of a 2x2x2 inch cube. The cube is meshed using Tet(10) elements and therefore is a 3D solid body. I apply a pressure to the opposite face and get the error as follows.
"NASTRAN Msg: ***WARNING: No element connection for node 1 directions 4, 5, 6
***WARNING: Similar warning suppressed for 313 other nodes.
NASTRAN Msg: ***WARNING: Nodal degrees of freedom without element
connection have been fixed for data input file.
This is a very confusing error message to me. When I mesh the box as a solid body, how are the elements not connected in some way ? The simulation will work if I apply two Enforced Displacement Constraints(the only displacements are in the X and -X directions with all others zero'ed) to the opposite faces but gives me an error when i attempt to Fix on face and load the other.
Any help is appreciated !





RE: NX non linear material FEM/Sim Problem
Make sure to include PARAM,AUTOSPC,YES in the Bulk data section, this way NASTRAN will remove all rotation DOF on solids.
Best regards,
Blas.
~~~~~~~~~~~~~~~~~~~~~~
Blas Molero Hidalgo
Ingeniero Industrial
Director
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