Cracked Pin-loaded Lug
Sample Applications
Cracked Pin-loaded Lug
Fatigue crack growth in a simple pin-lug model with contact between pin and lug
This example demonstrates fatigue crack growth of a mildly non-planar nature.
The model is a lug which is loaded by a tight fitting pin. Contact surfaces are defined between the lug and pin, including the region where the crack is initially located. The pin has constant amplitude loading in the 2 (Y) direction. The initial crack location is determined from maximum principal stresses in the uncracked model. The initial defect is a small through crack.
Animations of the crack growth are shown below in Figures 4, 6 and 7 and use displaced plots with a displacement magnification factor of 20 to help highlight the crack development.
Figure 1 - Complete mesh
Figure 2 - Uncracked analysis to determine maximum principal stress and hence a likely defect location
Figure 3 - Contact surface on the lug before (left) and after (right) insertion of the initial crack - confirming correct surface update
Figure 5 - Calculated growth profiles superimposed on the uncracked mesh - opacity view (left) and cut-away view (right)
Figure 8 - Comparison of growth results, da vs N, using Abaqus, Ansys and NX Nastran
Figure 9 - Comparison of growth results, Ki vs da, using Abaqus, Ansys and NX Nastran