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采用计算机流体力学对某双门四座敞篷轿车流场进行了数值模拟,研究发现敞篷轿车特殊的车身造型导致气流在前挡风玻璃后缘处分离,并在座舱内产生一对大尺度涡流和多个小尺度涡流.通过对比不同车速下敞篷轿车流场发现,随着车速的提升,由于舱内负压的增加,车身两侧气流向内弯曲的趋势明显,座舱中间区域的逆向回流范围变大.车辆在低速行驶时,座舱流场环境良好;车辆中高速行驶时,后排乘员头部两侧受车身两侧气流和逆向回流的影响较大.通过在头枕后方增加适当高度挡风板,可有效改善后排头部附近的流场环境,但导致了车辆风阻系数的增加;将后背高度提升至220mm时,后排座舱两侧气流和回流速度明显下降,整车风阻系数没有增加.
The flow field of a two-door four-seat convertible car was simulated by computer fluid dynamics. It was found that the special body shape of the convertible caused the airflow to separate at the trailing edge of the front windshield and generate a pair of large-scale eddy currents A small-scale eddy current.By comparing the flow field of convertible sedan with different vehicle speeds, it is found that with the increase of vehicle speed, the airflow in both sides of the vehicle tends to bend inwards due to the negative pressure in the cabin, When the vehicle is running at low speed, the cockpit flow field environment is good.When the vehicle is traveling at high speed, both sides of the rear occupant head are greatly affected by the airflow and reverse return on both sides of the vehicle body.By adding the appropriate height of the windshield , Which can effectively improve the flow field environment near the rear head but lead to an increase of vehicle drag coefficient. When the back height is increased to 220mm, the air flow and the backflow velocity on both sides of the rear cabin obviously decrease, and the drag coefficient of the whole vehicle does not increase .