CAE Analysis And Structural Optimization Of Motorcycle Frame

Frame is core part of motorcycle, which is involved in the safety and the comfortof the motorcycle and supports complicated loads.The strength,stiffness,as well asdynamic characteristicsare the important design indicators, finite element analysis andstructural optimization design of frame is carried out to improve the performance, whichis especially important in practical engineering.Taking a frame as an example, the geometric model of motorcycle frame isestablished using Pro/E software, then, the simplified mechanical model of frameisestablished.hypermesh software is used to mesh motorcycle frame, finite element modelof frame isbuilt,and then the static strength,stiffness,and the modal of the motorcycleframe are analyzed. Analysis results show thatthe maximum stress of frame are144MPa、164MPa、132MParespectively under the maximum horizontal load(conditionⅠ),the maximum vertical load(conditionⅡ), the maximum load of cushion(conditionⅢ),the maximum stress of frame is164MPa under the conditionⅡ,more than theallowable stress of material(159MPa), yield failure may be occurred to some of theparts of frame;In the analysis of the rigidity of the frame, the torsional stiffness of frameis910.7N·m/°, the bending stiffness is715.6KN/m,which are all beyond the normalscope of frame stiffness; first order natural frequency of frame is107.2HZ by modalanalysis,which is closed to the excitation frequency when the motorcycle is under topspeed, resonance may occur to the system.For the maximum stress of condition Ⅱexceed the allowable stress of material,stiffness is big, natural frequency is small, thesensitivity of various parts of the frame is analyzed, the optimization model is builtbased on the design variables is the parameters of components that have great impact onthe natural frequency and stiffness, based on the constraint condition is the maximumstress of three kinds of condition and stiffness,based on The optimization goal is naturalfrequency of frame.And then thickness parameter of frame assembly is optimized.Analysis results show that the maximum stress of three working conditions is140MPa、148MPa、108MPa respectively，which are lower than the allowable stress ofmaterial（159MPa）; The torsional stiffness and bending stiffness was reduced by23.36%and29.85%respectively, torsional stiffness of frame is in a reasonable range,butbending stiffness is still on the high side after optimizing. Quality of frame reducedfrom17.38Kg to17.38Kg, which is decreased by5.8%; Natural frequency of frame is 116.1HZ,which is increased by8.2%, dynamic performance of frame is improved.The research of this paper with the aid of finite element analysis method, inthe caseof meeting various performance indicators, to make the material designed for framebefull used effectively to shorten the development cycle and reduce research costs. Atthe same time, for enterprises to reserve the precious frame finite element model andrelated technical data,It has a certain reference significance for developing new framefor the future...