Lubrication Performance of Helical Gear Pair Under Dynamic Load Based on Local Involute Profile

Abstract

The tribological properties of gear interface have been widely concerned in the past decades. In this study, based on the local involute profile and crown modification, a thermal elastohydrodynamic lubrication model is proposed for a helical gear pair. To discuss the influences of dynamic load on the tribological properties of helical gear pair, the dynamic mesh force of tooth surface is obtained by torsional vibration model. The influences of working conditions and surface roughness on the tribological properties of helical gear pair are investigated. The tribological properties are evaluated in terms of the average film thickness, friction coefficient, mechanical power loss etc. Results show that the dynamic effect of gears has a significant effect on the tribological properties, especially at a specific speed, such as resonance speed. In order to simulation gear lubrication accurately, it is recommended to adopt local involute tooth profile and consider tooth profile modification to calculate geometric clearance. The influence of input rotation speed on the dynamic characteristics and tribological properties of gear is more significant than that of input torque. The surface roughness significantly changes the distribution of interface pressure and film thickness. With the increase of roughness amplitude, the local fluctuation amplitude of pressure and film thickness increase and the dry contact occurs at the end of contact line. Meanwhile, the maximum subsurface stress moves toward the tooth surface, especial for the high frequency engineering roughness. This local stress concentration is harmful to the fatigue life of gear meshing process.

Numerical Simulation of Fine Blanking Die Wear and Die Performance Analysis

“…e fine blanking process is studied by the finite element method, and the simplified model of undamaged punch is generally used [7]. Zhang compared the undamaged punch with the worn punch by finite element method.…”

Tribological characteristics evaluation of a helical gear pair based on the tribo‐dynamic model

“…F I G U R E 1 Schematic diagram of helical gear meshing and contact line on the plane of contact. 19 For gear lubrication, the formation of film thickness is due to the entrainment action of moving tooth surface. As most proposed gear lubrication models, [6][7][8][9][10][11][12][13][14][15][16][17][18][19] when the dynamic effect is ignored, the relevant kinematic parameters can be expressed as…”

“…Peng, et al 15 simulated the influence of modification and misalignment on the lubrication performance of helical gear. Based on transient thermal EHL model with the finite line contact theory, Liu, et al [16][17][18][19] systematically studied the influence of working conditions, geometric design parameters, oil supply conditions and surface roughness on the tribological properties of helical gear.…”

Tribological properties of a helical gear pair considering interfacial slip between lubricant and tooth surface

“…In the past decades, the non-Newtonian behaviour of fluid has been widely concerned in various lubrication 39 analyses. The constitutive equation of Eyring fluid is one of the most widely adopted in the published reports.…”

“…Zhou et al 38 proposed a numerical method to calculate the oil film stiffness and damping of gear tooth surface. Based on the local involute profile and crown modification, Liu et al 39 discussed the influences of dynamic load on the tribological properties of helical gear pair.…”