Modal Analysis And Reducing Vibration Optimization Of Powertrain Mounting System

The main function of the engine mounting system are supporting, positioning and vibration reduction, The key to improving vehicle ride comfort is configuring the automotive performance suspension system, which can also improve the car damping performance and enhance the market competitiveness of product45sthe main direction. It has a market value and practical significance of optimizing the design of powertrain mounting system.The paper takes the4D20powertrain suspension as the object of study, the powertrain is simplified as a combination of equivalent inertia and elastomers, suspension elements is simplified as the elastic springs which are along the space of three spindle directions. We try to build a powertrain mounting system equivalent model in ANSYS. The vibration isolation performance of the system is not ideal through our modal analysis. We take elastic element static stiffness and the installation location as the design variables, and take reasonable objective modal and higher decoupling as our goal. We use the random method to optimize modal, the optimized system has increased dramatically on each decoupling degree, the lowest value increased from36.56%to70.007%, the highest value increased to85.24%. The modal optimization results is obvious.To make the most of the damping performance of the suspension system, The subject take the working conditions of the maximum torque when the engine is working as an example, Minimize to center to the acceleration of the objective function of each elastic suspension elements, We have a modal damping optimization on the basis of model optimizing. After the vibration damping optimization, Every acceleration of the elastic element dropped significantly, the maximum value declined from118.391mm/s2to107.581mm/s2. The minimum value of the decoupling degree is70.76%, The modal frequencies are controlled within6-16Hz, The Z direction of modal frequencies avoid9～10Hz,and the decoupling degree is95.55%. The damping performance of engine mounting system can be further enhanced, so we can achieve the purposes of the optimized design.