摘要
以某轿车和卡车为研究对象,采用动网格和滑移交界面技术,对两辆车超车过程中外部流场进行了数值模拟研究,得到两车的阻力和侧力的瞬态变化趋势。同时通过截取流场剖面上的压力场和速度场,分析并总结超车过程中汽车的瞬态气动特性。仿真结果表明:在超车过程中两车周围的流场相互变化影响,车身受到的气动力在极短的时间内发生剧烈变化;两车的气动力变化趋势不一样,而且二者的变化不同步;轿车的气动阻力呈先增大,当两车车头的距离(X)与轿车车身长(L)之比为0.75时达到最大值,而后减小,最后恢复常态值;轿车的气动侧力有呈类正弦曲线的变化,即当X/L=-2.5和X/L=0.75时达到正向和反向的最大值;卡车的气动力变化趋势更复杂,且达到峰值的时刻与轿车的不同。
Employing the sliding interface and moving mesh technique,the 3-D transient external flow field around two vehicles overtaking each other was simulated.By analyzing the changing drag and side force and the pressure distribution and velocity vector on some sections,the transient aerodynamic characteristics of two vehicles overtaking each other were concluded.The results show that during the overtaking process,the drag and side force has a remarkable change in a short time.The forces of two vehicles do not have the same trend,and changes are not synchronized.The drag force of car increases firstly,and reaches its maximum when X/L=0.75 and then decreases,at last recovers to normal value.The tendency of changing side force of the car is similar to sinusoid,and reaches the maximum value of the forward and reverse when X/L=？2.5 and X/L=0.75.The variation tendency of force of the truck is more complicated,and the peak time points are different.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2011年第9期2681-2686,共6页
Journal of Central South University:Science and Technology
基金
国家自然科学基金资助项目(50975083)
教育部长江学者与创新团队发展计划项目(531105050037)
湖南省科技攻关计划重点项目(2009JT1014)
湖南大学汽车车身先进设计制造国家重点实验室自主课题(60870001)
关键词
汽车空气动力学
超车
气动力
动网格
automotive aerodynamics
overtaking
aerodynamic force
moving mesh
