Numerical simulation of wave propagation in cracked shafts

Abstract
The presence of crack-like defects in mechanical and structural elements produces failures during their service life that in some cases can be catastrophic. The increasingly importance of problems related with safety and costs derived from these catastrophic failures, have pushed the researchers in the field of damage detection, to look for and develop methods for the detection and identification of defects. The presence of cracks in rotating mechanical elements, such as shafts, is especially dangerous due to the fatigue effect generated by the work in bending and torsion together with the motion in rotation. In this work, the wave propagation in a cracked shaft due to an initial compression dynamic load has been numerically analyzed as the first step to establish a non-destructive method for the detection and identification of cracks using a dynamic test. Cracks with increasingly depths have been considered and studied. The same model has been submitted to an initial velocity. The results obtained in this work would allow the development of an on-line method for damage detection and identification for cracked mechanical elements using an easy and portable dynamic testing device.