Drag Reduction Effect Of The Truck Real Based On Non-smooth Surface Flaps

With the continuous development of China's economy,the car as the most important means of transportation,has become an indispensable part of people's life.However,the automobile consumption causes huge energy consumption,the exhaust emissions of cars have become the chief culprit of environmental pollution.At present, "energy conservation and emission reduction" are the strategic objectives and key technology research of the world, auto drag reduction and energy saving technology will surely become one of the most important topics.According to the research,60%-70% of the van's fuel is used to overcome the resistance in the process of driving.Van is the body of the truck,due to its larger windward area,when the speed is 100km/h,its aerodynamic resistance is about 75%-80% of driving resistance.So reducing the air resistance is imminent, t the same time,it is also the important way to reduce costs and increase the utilization ratio of fuel.The thesis is based on standard GTS truck model,the establishment of research for wagon flow field numerical simulation grid type and turbulence model on the basis of the design of the corresponding guide plate to reduce truck air resistance coefficient,and combined with the drag reduction mechanism of non-smooth surface guide plate for the quadratic optimization in order to achieve maximum drag reduction effect.the main contents of this paper are as followed:1.GTS standard model,numerical simulation is carried out,to compare the wind tunnel experiment data and the results of numerical simulation,it is concluded that using tetrahedron grid type and SST k- ? turbulence model,computing simulation more accurate.2.Studied the truck rear guide plate drag reduction effect,this paper uses three kinds of guide plate,by installing a different Angle and length of the guide plate,drag coefficient curve drawing,find the length of the guide plate and installation Angle of the optimal solution,and combining with the drag reduction mechanism of non-smooth surface of guide plate of quadratic optimization,in order to realize the maximum drag reduction rate diversion threatening the truck.3.The detailed analysis of guide plate and the non-smooth surface of the influence of the flow field and the body resistance.To illustrate various guide plate drag reduction effect,compared with the prototype,rectangular plate model and newmodel of the guide plate and the new model of the guide plate with groove to the rear of the longitudinal vortex,transverse section of vortex, pressure field,the pressure curve,turbulent kinetic energy distribution,etc.;At the same time studies the mechanism of drag reduction of non-smooth surface.4.The aerodynamic characteristics of some domestic van is optimized, and verify the trapezoidal guide plate and guide threatening the actual new models of drag reduction effect.