Simulation studies for determining the response characteristics of a hydraulic hybrid powertrain subframe

Abstract

Hydraulic drives are inherently heavy, and when such systems are combined with an internal combustion engine in a hybrid powertrain, the need to reduce mass becomes acute. This paper presents finite element models supporting weight reduction studies on a Hydraulic Power Assist (HPA) unit designed for use in a light-duty truck. Specifically, we determined the modal parameters and frequency response characteristics associated with critical structural components used to mount the HPA unit. Stress distributions, deformations, and strain energy distributions were computed for excitations arising from both vertical accelerations and harmonic forces. Results were used to evaluate weight-reducing design modifications.