Numerical Analysis for Wetting Behaviors of an Oil Jet Lubricated Spur Gear

Abstract

As it is widely employed in the aeronautical transmission system, a better understanding of the oil jet lubrication behavior is vital to determine the total system energy consumption. Firstly, this study presents related theoretical models such as the sum of oil jet resistance torque, impingement depth, and wetted area of the oil film for calibrating the physical characteristics of the impact of the oil jet on the gear flank. Then, in terms of the flow phenomenology of the liquid column for the oil jet impact on an isolated spur gear, a detailed transient and spatial flow field analysis becomes available, benefiting from an overset mesh method integrating with a volume-of-fluid (VOF) method. Furthermore, not only the oil jet resistance torque, but also the impingement depth as well as the spatial and temporal evolution of wetted surface by the oil film on the gear tooth given by numerical investigations were compared well with the theoretical calculations.

Performance of a New Aeronautic Oil-Guiding Splash Lubrication System

“…More than that, their study shows that a bigger oil jet angle contributes to a lower average resisting torque. Similar studies were conducted by Keller et al [21][22][23], with the SPH and the sliding mesh method, Ambrose et al [24], with the LBM method, and Dai et al [25], with the overset method. Among these, Kormer et al [26] proposed a theoretical model for predicting the heat exchange coefficient of the oil film on the gear surface combined with the impingement depth.…”

CFD Investigation on Oil Injection Lubrication of Meshing Spur Gears via Lattice Boltzmann Method

“…The rotating gears significantly affect the oil jet flow into the meshing area, which affects the lubrication and cooling performance of the high-speed gears, and can lead to insufficient lubrication or even gear scratches in the most severe cases. Nowadays, although high-speed spur gears are widely used in industrial applications, the flow mechanism of oil injection lubrication has not been fully revealed and the quantification evaluation method of jet lubrication performance is inconclusive, both of which have to be investigated further [1][2][3].…”