Composites-Orientation

Altair Forum User

Hi,

 

What is ply system ?

 

while assigning material orientation,we can select option,by assigning to elements or property.So we are actually defining the reference coordinate system for the ply angle(fiber direction).If assigned to property it is again assigned to elements.So eventually all elements will get the reference material orientation in what ever may be the reason.This assigns the MCID..also there is THETA that can be defined ?so do we usually define this...

 

But what is the ply system used for ?

Yea,ply can have element sets..so is this another way of referring the material orientation?

 

Can some one please clarify these.

 

 

Rahul_P1

Plates and shells can be made of layered composites in which several layers of different materials (plies) are bonded together to form a cohesive structure. each ply will have a different orientation as required to increase the overall strength of the system.Think of it as many layers of cloth stuck together, with each cloth having a different weave pattern for instance, this is what it is in reality, and this is what we must model hence we must use the ply system.

 

When you assign a material orientation, in the element for example (using MCID or Theta) you are defining the material coordinate system of the element. This is the basis for other definitions and also note that some results are output in material coordinate system as opposed to the elemental coordinate system.

The Ply angle is then input as the Orientation angle, in degrees, of the longitudinal direction of each ply relative to the x-axis of the material coordinate system associated with a given element.

 

So give element its material coord system definition > then create plies with orientations that are defined with respect to the material coord system definition.