Define composites materials with NX/NASTRAN

[DGia]

Hello,

I'm trying to simulate a cylinder made of composite material (PP resin with carbon fiber) wich is submit to a traction force.
It is the first time taht I perform a composite material simulation.
I meshed the cylinder with HEXA8 elements, I have constrained in all translation one planar face and on the other one I have apllied a force.

I think I have a problem with material definition. If I'm not wrong, there are 2 methods to define composites materials :

_ The first one is to determinate the caracteristic of the composite material (E1, E2, G12, v12, etc.) and then we define the plies (angle, thickness). In according with the characteristics of the material and the characteristics of the plies (angle), NX calculate the mechanicals characteristics of each ply.

_ The second one is to define the characteristics of fibers (E, density, etc) and resin (E, density, etc) and the volumic fraction of each one. We need to specify the angle and thickness of each ply too. In according with these entries, NASTRAN defines the mechanicals characteristics of the whole composite material.

I've defined the composite material with the second method, but I've a fatal error message :

*** USER FATAL MESSAGE 4654 (EPENLGC,STS268)
THE STACKING DIRECTION FOR THE COMPOSITE PENTA
ELEMENT ID %1 IS ONLY
SUPPORTED ALONG THE NORMAL DIRECTION OF THE TWO
TRIANGULAR FACES

I've undertand that I've a problem with the stacking directions of plies. I setted the ply direction along the "Z" axis and the stacking direction along "Y" axis. I've already tried to change the stacking direction to "Y" in "X" axis, but doesn't work.

Anyone can help me please ?

Thank you four your helps !

 

[Zadrobu]

Have you tried specifying a cylindrical coordinate system in your material property cards?