Stack direction of cohesive element

[seababy]

Dear all,

I use the cohesive element to model the crack penetration in film/substrate system(2D problem). The cohesive layer is implemented along -y direction, and the stack direction(thickness direction) is required in -x direction, but by default the stack direction is in -y direction for 2D cohesive element. I added the key word "*COHESIVE SECTION, STACK DIRECTION=1" according to the manual, but it did not work. Can anyone tell me how to specify the stack direction?

Tons of thanks!

Mei

 

[yanyabin]

Hi

I used to meet this problem and the method of using key word did not work in my simulation.

Here I want introduce a method which may cost a lot of time if you have many cohesive elements in your model.

As I know, the stack direction is related to the arrange sequence of nodes in cohesive elements. Therefore, by rotating the nodes to change the stack direction of cohesive elements. such as:

original sequence:
4-3
| | stack direction is from node 1 to node4 at this time,
1-2 it is vertical!

Then rotate the nodes as:
3-2
| | stack direction is still from 1 to 4, but it is
4-1 horizontal now! The direction is changed!

The disadvantage of this mehtod is that you have to rotate every node of cohesive elements, which will cost a lot of time. However, you can do this work in EXCELL and then you can rotate all of cohesive elements by changing the sequence of vertical node lines at one time and will save a lot of time.

I am sorry for my bad english and i hope this will do some help to you.

Regards

yanyabin