Hello,

I am trying to calculate J-integral and Energy release rate of an actual crack (not a crack growth model) by using ANSYS. Pre-Meshed cracked is the method I selected. However, for two same length crack, but just open in different direction, ANSYS gave me a total different result of G ( energy release rate).

Condition set: fixed support at bottom and 1 micrometer y direction displacement at top

1. Crack open at left side

Total deformation as following:

And I got J-integral = 66.19 and G total = 64.233

2. Crack open at right side

Total deformation as following:

And I got J-integral = - 66.188 and G total = 0

Why changing crack open direction will lead to a zero energy release rate result? Please help me if you met similar situation before and know how to solve it.

Thanks a lot!

Sylvia