Aero-Thermal Optimization of a Hybrid Roadster Tricycle Using Multidisciplinary Design Optimization Tools

To reach the goal of continuous improvement on automotive vehicles, their overall design strategy needs to be reconsidered. Hence, the future design will have to use global approaches like those developed in the aerospace industry where optimization of all interacting fields is performed jointly. This strategy has been applied to the development and optimization of a hybrid roadster aero-thermal management as part of a major Automotive Partnership Canada (APC) project¹. The study presented herein seeks the best compromise between the vehicle aerodynamic drag and the cooling efficiency for the internal combustion engine (ICE) and the electric motor. The optimization of the heat exchanger position is first achieved followed by a multidisciplinary design optimization (MDO) approach with three main steps: first, a design of experiment (DOE) involving parametric CAD model generation, steady state CFD calculations and a heat exchanger optimization loop; secondly, approximations of response surfaces methods; finally, multi-objective optimization on the response surfaces using genetic algorithms and particle swarms. The study is constrained to use the automotive manufacturer’s software and to consider the vehicle environment without bringing significant modifications on non-thermal/aerodynamic parts.