The effect of three-dimensional crack growth on the force distribution and meshing stiffness of a spur gear: Ideal and misaligned contacts

Abstract This article presents a routine for prediction of the crack growth path in gears. Crack simulation helps in determining failure modes and crack detecting by vibration monitoring. To simulate crack propagation an effective method is developed by which the meshing force is calculated based on the compliance of meshing teeth in every stage of crack growth. In this method the compliance matrix of the tooth is calculated using three-dimensional boundary element analysis without the need for simultaneously modelling two meshing gears. The force distribution on the contact area is then calculated using Hertz theory and compliance matrices of meshing teeth. The method is used in prediction of the crack propagation path, meshing force, and meshing stiffness for two cases of ideal and misaligned meshing of a spur gear set. The crack propagation path is very different in the two cases of meshing and affects force distribution on a contact zone. Meshing stiffness reduces as crack propagates but the amount of reduction depends on the position of the contact line and crack propagation path.