Abstract:Based on the flow field lubrication of the incompressible gasliquid twophase flow in the gear box,the VOF(Volume of Fluid Model) was used to track the free liquid surface,and PISO (PressureImplicit with Splitting of Operators) and dynamic grid technology were used to calculate the internal flow field of the gear box.The influence of driving speed,forward and reverse rotation and oil injection on the instantaneous distribution of oil inside the gearbox,the internal pressure distribution of the gear box and the mass flow of the bearing hole were analyzed.The results show that with the increasing of the driving speed,the internal lubrication of the gearbox is more timely and effective,the internal pressure of the gearbox is increased,and the mass flow rate of lubricating oil in all the oil inlet of the bearing is increasd.It is more conducive to the oil diffusion in gearbox with the increasing of the oil injection,and the mass flow rate of lubricating oil in all the oil inlet of the bearing is also increasd,while the increasing of the oil injection has little influence on the pressure distribution.The effect of positive and negative reversal on the oil distribution is small,there exists the maximun positive and negative pressure when the gear turns counterclockwise.The gear negative pressure has obvious change with the increasing of the driving speed.