Influence of oil injection methods on the lubrication process of high speed spur gears

Computational fluid dynamics simulation is used to establish models for different oil injection methods: into-mesh and out-mesh injections. The simulation results concluded that when the gear pitch line velocity is higher than the velocity threshold, the oil jet cannot reach the meshing point when the out of mesh jet lubrication is used. When the ratio of the pitch velocity to the spray velocity is less than 5, better lubrication are obtained by out of mesh jet lubrication. When the ratio of the pitch velocity to the spray velocity is more than 5, into mesh jet lubrication can achieve better lubrication. Finally, the influence mechanism of different oil injection methods on lubrication process is revealed through theoretical analysis.