Optimization of the Underbody Layout of a Small Van for Better Aerodynamics Using Digital Simulation
The Wuling Rongguang is a small van which uses a mid-engine layout where the engine is located underneath the floor panel in-between front and rear wheels. A particular challenge for this kind of layout is the protection of the engine against soiling. Typical protective measures consist of large mudguards in combination with an engine cover. While needed for soiling protection, these parts can have a strongly adverse effect on aerodynamic drag. This paper describes process and the results of the aerodynamic optimization of the underbody of the Wuling Rongguang. Because design changes had to be evaluated for aerodynamics performance as well as for their effect on the soiling, a digital approach was used which allowed to do the soiling analysis as a post processing to the flow simulation. As a first step, a baseline model was built and analyzed. This included the development of a soiling model taking into account wheel spray and splashing effects.