Aerodynamic Optimization for Car Body Under Constraints of Inner Space

Abstract:

The process costing genetic algorithm combining with the constraint operator of inner space based on vehicle ergonomics is used to optimize the aerodynamic performance of car body. Three dimensional optimizational car bodies without wheels satisfying constraints of inner space with different structures and sizes are obtained. The coefficients of aerodynamic drag (CD) of those optimized car bodies are within the confines of 0.070 to 0.090, and their aerodynamic performances are all good. Under the constraints of inner space which comprises long fore capsule, big crew capsule and high rear capsule, a cheese head optimized car body whose CD is 0.0728 and a socket head optimized car body whose CD is 0.0860 are obtained. When the size of inner space constraint is smaller and the structure is simpler, the aerodynamic optimization result is better. When the style of the car body is more complex, the constraint of inner space makes a greater difference to the aerodynamic optimization results.