A low-cost morphing vehicle design for enhanced aerodynamic performance

Abstract

Mid- and large-size road vehicles are responsible for high levels of green-house gas emissions, due to their poor aerodynamic designs. To alleviate this environmental and health risk, we propose a low-cost, noninvasive morphing vehicle design toward improved aerodynamic efficiency and reduced emissions. Using a generic pickup truck as the base geometry, morphing is accomplished by retrofitting a flexible structure over its cargo bed region, enabling active deformation and interaction with the airflow. The shape morphing process is optimized through a combined parametric genetic algorithm – computational fluid dynamics framework, enabling continuous morphing across a range of driving speeds. The optimal structural shapes lead to a reduction in the aerodynamic drag force between 8.7% and 10.1%. Analysis of the airflow physics reveals that the morphing structure compresses the size of the circulation bubble and reduces the strength of the counter-rotating flow structures in the wake, resulting in increased wake pressure and decreased drag force. Remarkably, the morphing structure not only reduces the drag on the base vehicle geometry but also elicits a negative drag force on itself. This non-invasive morphing vehicle design concept could transform the automotive industry by enhancing fuel economy and reducing emissions for existing vehicle models.