Influence of profile modifications on spur gear sliding power losses: an integrated approach with advanced mesh stiffness and partial EHL

This study investigates the impact of profile modifications on sliding power loss in cylindrical gears, a critical aspect of gear efficiency. Profile modifications are widely adopted in gear design to improve load distribution, mitigate noise and vibrations, and enhance durability. Although much of the existing research has focused on their dynamic benefits, such as reducing noise and vibration, their influence on gear meshing efficiency, particularly sliding power losses, remains insufficiently quantified. Leveraging an original advanced mesh stiffness model sensitive to microgeometry modifications, this work integrates an analytical load-sharing model with a partial elastohydrodynamic lubrication framework to evaluate the instantaneous friction coefficient. The analysis reveals that certain profile modifications, specifically tip relief and profile barreling, can significantly reduce sliding power losses, often by more than 20%. In contrast, pressure angle modification has a negligible effect on power loss, especially at higher torques. These findings demonstrate that profile modifications can substantially alter gear mechanical efficiency and must be considered in design. Neglecting them may lead to significant over- or underestimation of energy losses. Although based on static analysis, the identified trends are robust and generalizable across gear types and load conditions.