Based On The Fracture Failure Of A Turbine Starter Ring Gear Of The Nonlinear Study Analysis

Turbine start machine is a very important composing part for aero-engine,the transmission of turbine start machine is a two-stage gear train,its dynamics behavior and work capability is very important to machine .Some turbine start machine have occurd malfunction because the tooth circle of fluid force coincidence implement took place rupture during the start process.therefore,the research to of the transmission system have important theory meaning and engineer utility valu(?).This dissertation mainly do some research aim at the transmission system of the turbine start machine. Established the non-linear dynamics model of a two-stage gear train with backlashe between the gear pair,on this basis, the dynamics characteristic research of the system are performed .Firstly,using the method of concentrate mass this paper establish a non-linear dynamics model of a two-stage gear train with backlashe between the gear pair,and through analysed the dynamics model,the torsional motion differential equations are got , on this basis,then calculate the torsional motion differential equations using Runge—Kutta method ,and discuss how to influence the dynamics characteristic of system when these parameters chage such as mesh frequentcies, stiffness of the intermediate shaft,the ration of mesh frequentcies.and discuss when the chaos will happen under the change of these parameters.Through analyse the result of a two-stage gear train with backlashe between the gear pair include time history, phase plane diagram,fourier spectrum, poincare section,and derives the dynamic response for for dynamic excitation.Confirm the dynamic load coefficient and dynamic load of the gear train,fmally,emendate the intensity of tooth circle of fluid force coincidence implement, the calculate show that because the system response is chaotic response,so the dynamic load coefficient is too large,bring on the tooth bend stresss of the fluid force coincidence implement is larger than the allow bend stresss ,this is the mostly reason lead to the tooth of the fluid force coincidence implement happen break.Through analyse the contact stress of tooth and pin use ANSYS,we discuss the infection of mesh position and pin amount to the stress of tooth .Add analyse the manufacture technics of tooth ,we educe that the manufacture technics isn't eligibility prick up the tooth break.finally summarize which condition that the malfunction will occur and put forward amelioration project.