基于CFD的某特种电动汽车空气动力学分析与改进设计

Aerodynamic analysis and improved design of a special electric vehicle based on CFD

为降低某特种电动汽车空气阻力,对其车身造型进行了改进设计。对初始设计的汽车模型进行CFD外流场仿真分析,得出其风阻系数为0.4173,车顶前端、前窗和尾部等有明显的涡流。选择车顶倾斜角α(1)、前窗玻璃角α(2)、前唇倾角α(3)、后背角α(4)和尾部上翘角α(5)为设计变量,仿真分析车身外形局部结构参数对汽车气动特性的影响,并提出了改进设计方案。仿真结果表明:改进后车身升力系数的绝对值为0.1141,相对初始设计提高了41.92%;风阻系数为0.3937,相对初始设计降低了5.66%,有效改善了汽车的气动特性,提升了其续航能力。

In order to reduce the air resistance of a special electric vehicle,the body shape of a special electric vehicle was improved.Through CFD simulation analysis of the initial design of the body outflow field,the wind resistance coefficient was 0.4173,and there were obvious eddy currents at the front end of the roof,front window and rear.Roof tilt angleα(1),front window angleα(2),front lip tilt angleα(3),rear back angleα(4)and tail upturn angleα(5)were selected as design variables.The influence of local structural parameters of the body shape on the aerodynamic characteristics of the vehicle was simulated and analyzed,and the improved design scheme was determined.The simulation results showed that the absolute value of the lift coefficient of the improved body was 0.1141,which increases 41.92%compared with the original design.The wind resistance coefficient was 0.3937,which was reduced by 5.66%compared with the initial design,effectively improving the aerodynamic characteristics of the vehicle and enhancing its endurance.