CAE frame work for aerodynamic design development of automotive vehicles
Maximizing fuel efficiency of a vehicle is one of the prime areas of focus in the highly competitive automotive industry which requires development of efficient and optimized vehicle designs. External aero analysis using Computational Fluid Dynamic (CFD) techniques is widely used in the accurate estimation of an automotive vehicle’s drag coefficient, often critical in determining the fuel efficiency of the vehicle and thus drives the design development process. In a typical design process, several design variations are analysed, their effect on specific parameters such as the drag and lift coefficients is studied, and thereby, an optimum vehicle design is developed. Numerous techniques can be used to develop design variations from an existing design and to perform design development studies.
Morphing is one such technique that offers significant advantages. Using Morphing, design variations can be developed very easily and quickly with minimal effort. In addition, statistical methods can be used to establish correlation between shape change parameters and performance parameters, such as the drag coefficient, to generate optimum design.
In this paper, Meshing and Morphing tools in ANSA, a commercial Computer Aided Engineering (CAE) pre-processing software developed by BETA CAE Systems S.A., are used to develop the baseline Computational Fluid Dynamics (CFD) mesh model and subsequent design variations from the baseline model. Statistical analysis methods are then used to establish a correlation between the geometrical parameters and the drag coefficient to guide the design (shape) development of a General Motors’ (GM) automotive vehicle.