Nonlinear dynamic characteristics of planetary gear transmission system considering squeeze oil film

Abstract

Based on the planetary gear transmission system considering the coupling effects of friction and elastohydrodynamic lubrication, a torsional dynamic model considering friction, oil film, time-varying meshing stiffness, meshing damping, and gear backlash is established. The Runge–Kutta numerical method is used to solve the vibration equation of the system. The bifurcation diagram and largest Lyapunov exponent are used to analyze the dynamic characteristics of the system under different bifurcation parameters such as the excitation frequency, lubricant viscosity, sun–planet backlash, and planet–ring backlash. The numerical results demonstrate that with the increase of excitation frequency, the system exhibits rich nonlinear dynamic characteristics such as short-period motion, long-period motion, and chaotic motion. With the increase of lubricant viscosity, the chaotic motion of the system is suppressed at low excitation frequency and the periodic motion of the system increases at high excitation frequency. With the increase of sun–planet backlash, the chaotic motion of the system increases at low excitation frequency, and the bifurcation characteristics become complicated at high excitation frequency and enters chaotic motion in advance. With the increase of ring–planet backlash, the system delays into chaotic motion at low excitation frequency and bifurcates from single-period motion to multi-period motion in advance at high excitation frequency.

Research on nonlinear dynamic characteristics of high-speed gear in two-speed transmission system

“…T c1 is the friction torque of the inner gear ring and the planetary frame, which is related to the pressure applied by the friction clutch, the number of friction plates and the friction coefficient of the friction plates, as shown in Eq. (6), where R o is the radius of the outer circle of the friction plate, and R i is the radius of the inner circle of the friction plate. T L (t) is the load torque applied on the output shaft of the driveline.…”

“…Li5 studied the meshing characteristics of planetary gear train when the position of the planetary frame changes under variable loads. Wang6 established a torsional dynamics model of planetary gear transmission system considering friction, time-varying meshing stiffness, meshing damping and clearance, solved the system vibration equation by Runge-Kutta method, and analyzed the bifurcation and chaos characteristics of the system through bifurcation diagrams and phase diagrams. Luo 7 established a dynamic model including time-varying meshing stiffness, sliding friction and torque, and studied the influence of sliding friction on the dynamic characteristics of planetary gear mechanisms.…”

Nonlinear characteristics of a multi-degree-of-freedom wind turbine’s gear transmission system involving friction

“…The dynamic behaviors were investigated in different system parameters. Wang et al [5] established the planetary gear transmission system considering the coupling effects of multiple nonlinear factors. The Runge-Kutta numerical method is used to solve the system vibration equation.…”

Analysis of nonlinear dynamic characteristic of a planetary gear system considering tooth surface friction

“…39 Luo et al 40 established a planetary gear set dynamic model with spalling defects and sliding friction, and found that spalling defects and sliding friction have a significant effect on the dynamic response of the planetary gear set, and finally verified the dynamic model through experiments. Wang et al 41 established a torsional dynamic model considering friction and squeeze oil film. The dynamic response of the system is obtained by a numerical solution, and the influence of lubricating oil viscosity, sun-planet backlash and ring-planet backlash on the system was studied.…”

“…The dynamic response of the system is obtained by a numerical solution, and the influence of lubricating oil viscosity, sun-planet backlash and ring-planet backlash on the system was studied. 41 Wang and Zhu 42 established a dynamic model of the spur planetary gear-rotor-bearing of the geared turbofan (GTF) gearbox, and analyzed the dynamic response of the star bearing under different friction coefficients using a three-dimensional frequency spectrum, and finally found that the star-bearing stiffness frequency experiences surge under an increasing frictional coefficient.…”