The Research On Air Flow Of Van Equipped With Different Forms Of Wind Deflector

Since the invention of automobile,the human society has entered an era of rapid development.As of the end of 2016,the number of national motor vehicle is up to 290 million,including twenty-one million four hundred and thirty thousand trucks.Energy consumption and environmental protection has become the focus of the world.Scholars work harder in order to reduce energy consumption and improve the environment.Especially research on Vehicle energy saving and emission reduction and aerodynamics in improving the vehicle running resistance.The shape and windward area of vehicle is two main variables influencing for air resistance,at a certain temperature,air density,wind speed,and speed conditions,change the shape of the vehicle can significantly reduce the drag coefficient,so as to achieve the effect of energy saving and emission reduction.This paper studies the influence of vans air flow-field and drag coefficient by the wind guide plate with different forms using numerical simulation method.And research the performance of deflectors with different forms on the vehicle,design a better shape of wind guiding plate;This study is to numerically study the air flow-field distribution and the drag coefficient of the tractor-trailer vehicles with deflector installed.The aerodynamic effects for different type of deflectors are analyzed to obtain a better deflector design.Three CAD/CAE software including pre-processing software,CATIA,CFD software FLUENT,and post-processing software TECPLOT,is used to perform the three-dimensional numerical computation,and the analyses are performed at the speed of 5 m/s.The results show that among the three basic types of deflector,the drag of the arc-shape deflector is the lowest.Research results show that quadratic function surface wind guide plate was the best in three basic forms.After smoothing and change the direction angle the wind guide plate,wind resistance decreased obviously.After fillet edge processing,the drag can be reduced further.The results show that the drag coefficients can be reduced from 4% to 17% when different deflectors are installed in the vehicles.There is also an angle limit for the deflector to contract,expand or installed.