Analytical Design and Development for Automobile Powertrain Mounts Using Low Fidelity Calculators

摘要

The excitation to a vehicle is from two sources, road excitation and powertrain excitation. Vehicle Suspension is designed to isolate the road excitation coming to passenger cabin. Powertrain mounts play a vital role in isolating the engine excitation. The current study focuses on developing an analytical approach using Low-Fidelity computer programs to design the Powertrain Mount layout and stiffness during the initial stage of product development. Three programs have been developed as a part of this study that satisfy the packaging needs, NVH requirements and static load bearing requirements. The applications are capable of providing the Kinetic Energy Distribution and Static Analysis (Powertrain Enveloping and Mount Durability) for 3-point and 4-point mounting systems and the ideal mount positions and stiffness for 3-point mounting systems. The decoupling analysis for ideal mount positions and stiffness is based on the Torque Roll Axis (TRA) decoupling scheme wherein the optimal mount locations and mount stiffness are predicted for 100 percent decoupling of powertrain modes. The Static Analysis application allows the user to predict the displacements and forces coming on the mounts under static loading conditions with Linear/Non-Linear spring characteristics. The programs are developed to provide baseline solutions much before detailed CAD data are available. The programs are further coupled with an Analytical Enterprise Level Calculations Management System to provide the designer with an easy-to-use GUI and capabilities to compare and evaluate multiple designs along with one-click report generation. In totality, they act as a toolkit to provide concept-stage solutions to Powertrain Mount design.