The3D Model Establishment And Flow Field Simulation Analysis Of Motorcycle

With the rapid development of motorcycle industry, our country has become the first country of motorcycle product in the world in the last decade. Motorcycle industry still has a broad prospect, so it is quite necessary to increase more independent researches to motorcycle. Meanwhile, materials and energy prices continue to rise in recent years, thus energy-saving, environmental protection have been paid more attention in the motorcycle industry. As the motorcycle aerodynamic performance is closely related to energy-saving, environmental protection, safe driving, etc, so more researches on the aerodynamic performance of the motorcycle should be done during the independent development design of new motorcycle product. And we can apply the research results in motorcycle to design the low oil consumption, good streamline appearance motorcycle products.Based on the CFD numerical simulation method, we do research on the aerodynamic performance of motorcycle, analyze the pressure, velocity, turbulent flow field, and conclude the variation of the motorcycle’s flow field. First converse design is taken according to the clay model of the motorcycle, including data acquisition and surface reconstruction process, and then a suitable three-dimensional model is established with CATIA software. After that the model is moderately simplified to make sure that the model is meshed smoothly and computed convergence. Finally, a detailed analysis and discussion is carried out on the flow field when the driver driving motorcycle.The research shows that, while this motorcycle is running the drag coefficient is0.709and lift coefficient is0.147, and the front part of motorcycle and human body accounts for a major portion of the stress the model suffered from. The aerodynamic force of the model rises with the approaching flow’s velocity increases while the drag coefficient and lift coefficient doesn’t change at all. Plus the lateral force, yaw moment, longitudinal pour moment and heeling moment of the model increases with increasing of side wind’s yaw angleβwhich have a great influence on the stability and comfortableness of the motorcycle. At last, based on the results of CFD analysis, a reasonable modeling scheme is proposed for improving the aerodynamic performance of the motorcycle. When the inclination angel of headlights cover is53° and there is a shunt hole in the front part, the aerodynamic drag coefficient of the motorcycle model reduces to0.667, reduced by5.25%compared with the original model; the lift coefficient reduces to0.131, reduced by10.88%compared with0.147of the original model.At the initial stage of product design of motorcycle, do researches on motorcycle aerodynamics with CFD numerical simulation method is time-saving, labor-saving and greatly accelerates the development speed of new motorcycle product: The research results also provide a reference for the design of the motorcycle, and broaden the application of CFD numerical simulation in motorcycle industry.