# 3D crack analysis using ansys

## How to extend crack in Mixed mode crack growth in Ansys ?

Hi, I am doing project on mixed mode crack growth of semi elliptical crack in gas turbine components under cyclic loading. Ansys has capability for finding J,K using CINT command. But, In mixed mode crack growth, i dont know how to deal with nodes and how to create random crack with new node coordinates obtained from previous steps. If you have any ansys code related to creating crack and finding fracture parameters like K, J (mode 1 or mixed mode), Can you please give me the code.

Thanks

(I cant use any other software, only Ansys)

## Can any one provide any apdl code to perform automatic fatigue crack growth ??

Hi, I am using Ansys Apdl for 3d fatigue crack growth. I need any one code to understand how it can be automized (recreating crack with node shift and remeshing).

Thank you

## use of CINT command for J integral calculation of 3d model with ansys

I used for the first time the CINT command with ansys, and I get strange results:

negative values

very different values for 2 adjacent nodes on the crack front

non converging values (values fluctuating from 1 contour to another, going up and down)

Also, i don't know what are the units of the J integral (I am using SI units, dimensions in mm ).  It's important to know so I can calculate the SIF

How can I know what contour gives the best result? what are the units of the Jintegral in the SI.

Anybody have some information for me?

## 3D modelling of an ellliptical crack in ANSYS

I am a beginner in FEM and just started using ANSYS.  I need to study the stresses and SIF at the crack front of an elliptical crack inside a material subjected to a stress perpendicular to the crack plane.  Any details on how I should build my model?

What is the easiest way to define a cracked area, and crack front and then mesh it

How can i merge together a cracked area and an unmeshed area?

I found a lot of links and articles that states they did it, but none explained the procedure do do it.

Thanks

## poissons ratio effect on Stress intensity factor

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Hi :

I am obtainning the Stress Intensity factors along the front of cracks in a 3D FE models (ANSYS). The loading mode is mixed and Ki, Kii and Kii should be estimated. I have noticed that the SIF  strongly depends on the poisson's ratio but i understand Ki does not depends on the elastic properties of material. I know ANSYS calculates the SIF from the displacements at the crack tip using E and mu, but i did not expect so huge differences in SIF values, In fact all analytical predictions for SIF does not depends on poisson's ratio....

## 3D Crack analyses using ANSYS

i m dan doing ME Engineering Design.I m doing project in the area of probabilistic fracture mechanics.,So i need how to find SIF,J integral,Energy release rate,CDOT  for all type of crack (2D,3D)..,I want some of the material related to this..,i m using Ansys..,so complete step by step procedure in Crack analysis using analysis i want 3d Crack analysis