Fracture Simulation Of Engine Mount Components And The Establishment Of The Mounting Bracket Load Spectrum

With the development of economic and continuous improvement of road traffic environment, and even the energy, pollution problems have become increasingly prominent, the trend of automobile design shows characteristics with light weight, high torque and economic, which deteriorates the vibration characteristics of cars to a large extent, and seriously affects the ride comfort of vehicles. As the car engine is the main excitation source of motor vehicles, mounting system is to isolate the vibration between engine and chassis. The merits and demerits of the system performance is directly related to the vibration and noise level of the car. Therefore, the research for mount system of engine is very important.At first, this paper make a comprehensive exposition about the research content and progress of automotive engine mounting system, on the basis of the conclusion of our predecessors on the mounting system, it carrys on the research from suspension components and the fatigue failure of mounting bracket, discusses the characteristics of fatigue failure about the rubber mount and hydraulic suspension, simulates the fracture and establishes the load spectrum of support test. This paper includes the follows:(1) The research progress of the mounting system was introduced, several structural forms and working principle of the rubber mount and hydraulic suspension was compared and analysised(2) The engine mount components was analysised with nonlinear finite element method. First of all, the3D model of the finite element model was established. Secondly,it was analysised with nonlinear finite element method. Finally, according to stress cloud image, the initial position of cracks and the fracture surface was identified.(3) The load spectrum of automotive engine mount bracket was established. First of all, the engine mount bracket was analysised with FEM and the key points of fatigue was identified.Secondly, the damage of the measuring points were calculated with the measured load spectrum and the stress spectrum of the key points. Finally, the load spectrum was calibrated in accordance with the principles of injury consistent. The damage of the key points caused by the calibration load spectrum was consistent with the actual situation.(4) The fracture processes of the rubber mount and hydraulic suspension along the predicted fracture surfaces was simulated and reproduced with the cohesive element of ABAQUS software.