| Dynamic and lubricating characteristics determine the efficiency and life of gear drive system to a great extent.For the high-speed heavy-duty gear drive systems,the incentive of inertia force,damping and stiffness have significant effects on its transmission characteristics.Therefore,vibration and lubrication effect should be considered simultaneously,and the coupling study of dynamics and elastohydrodynamic lubrication(EHL)must be carried out.The focus of this article is aeroengine gear drive system.Firstly,the lubricating characteristics of gear system under the effect of vibration and contact impact coupling was studied.On the basis of dynamic excitation of gear meshing stiffness and the dynamic theory of gear system,a kinetic model considering tooth surface friction was established.On this basis,the contact impact(collision)phenomenon of driving gear caused by sudden change of speed at a certain instant was studied.The influence of different contact impact position and impact speed on dynamic load was compared,and the influence of dynamic load and steady load on lubrication was analyzed.The coupling of gear system dynamics and lubrication under different loads and speeds was studied.Based on the dynamic excitation effect of meshing stiffness and the theory of gear system dynamics,the kinetic model,lubrication model and lubricating film stiffness model of gear system were established.The study of tooth lubrication and gear system dynamics coupling was carried out.The tribological performance of tooth surface(lubricating film thickness,pressure and temperature rise ratio),lubricating film stiffness and the influence of oil film lubrication on the dynamic loads of gear mechanism were analyzed.The research of dynamics and tooth surface lubrication coupling of modified gear system under thermal condition was carried out.Considering the influence of different gear transmission types and modification coefficients,based on the excitation effect of gear time-varying meshing stiffness and gear system dynamics theory,a kinetic model considering the effect of tooth lubrication was established.The study of tooth lubrication and gear system dynamics coupling was carried out.The lubricating properties of tooth surface under dynamic loads and the effect of lubrication on the dynamic loads of gear mechanism were analyzed.Research on coupling of gear system dynamics and magnetic fluid lubrication.Taking the effects of the base carriers of different magnetic fluids under the condition of no magnetic field and the effects of different magneto-induction strengths under the condition of magnetic field into account,On the basis of excitation effect of gear meshing stiffness and the dynamic theory of gear system,the magneto-fluid lubrication model and kinetic model were established.The influence of different magnetic fluid base carriers and magnetic induction intensity on the viscosity of lubricants,lubricating film stiffness,dynamic loads distribution and tooth surface tribological performance were analyzed. |
