Effect of localised tooth spall defect on dynamic performance of a high-contact-ratio spur gear system

Abstract This study considers the tooth spall morphology and establishes a kinetic model of a high contact ratio gear pair system with an ellipsoid tooth spall defect. The mesh stiffness of the spalled gear system is evaluated using the potential energy method. To obtain the accurate dynamic response, the friction force was incorporated into the gear kinetic model. The dynamic transmission error and dynamic meshing force under different rotational speeds are acquired by the proposed model. The dynamics of a healthy gear system and spalled gear system was compared. The results reveal that the presence of the tooth spall defect alters the motion state of the system, making it prone to instability. The study provides a theoretical foundation for future research on spall defect diagnosis of gear transmission devices.