Elastohydrodynamic Lubrication Damping of Spiral Bevel Gears at Moderate Loads

Modeling of elastohydrodynamic lubrication phenomena for the spiral bevel gears is performed in the present study. The damping and the friction coefficient generated from the lubricated contact area will have profound effects on the dynamics of spiral bevel gears. Thus the damping value generated from this friction model will be time varying. This makes the use of constant and empirical damping value in the dynamics of spiral bevel gears questionable. The input geometric and kinematic data required for the elastohydrodynamic lubrication (EHL) simulations are obtained using Tooth Contact Analysis. A full numerical elastohydrodynamic lubrication simulations are carried out using asymmetric integrated control volume (AICV) algorithm to compute the contact pressures. The fast Fourier transform is used to calculate the elastic deformations on the gear surfaces due to contact load. The computed pressures and the effective viscosity are used to calculate the time varying damping for the spiral bevel gears. Parametric studies are also conducted by varying the rolling velocities, lubricant properties and torque load to explain the effect of lubrication on the spiral bevel gear dynamics response.