基于多岛遗传算法的汽车车身气动优化

为研究不同长细比汽车车身的最优气动性能，基于英国汽车工业研究协会(Motor Industry Research Association, MIRA)阶背模型，利用多岛遗传算法开展不同长细比的汽车车身气动优化.优化结果表明优化模型的气动阻力因数随着长细比的增大而降低.通过改变车身的长细比得到的5种优化模型具有发动机罩倾角、后风窗倾角和尾部上翘角较大，前风窗倾角较小的特点.对8个优化参数进行分析可知：尾部上翘距离和前悬距离对气动特性的影响最大.

Aerodynamic optimization on automobile body based on multi island genetic algorithm

To study the optimal aerodynamic performance of automobile body with different slenderness ratio, based on the hatchback model of Motor Industry Research Association(MIRA), the aerodynamic optimization on automobile body under different slenderness ratio is studied by multi island genetic algorithm. The optimization results indicate that the aerodynamic drag factor is decreased with the increase of slenderness ratio. Five optimization models are obtained by changing the slenderness ratio of automobile body, of which the engine hood angles, rear window angles and rear diffuser angles are larger and the front windshield angles are smaller. The analyses on eight optimization parameters show that the distances of rear warping and front suspension have great effect on aerodynamic characteristics.