客车铝合金车身连接件多目标优化

Multi-objective Optimization of Aluminium Alloy Body Joints for Buses

铝合金客车车身多采用机械连接的方式,连接件的设计质量直接关系到铝合金客车的刚度、强度、模态及轻量化等方面的综合性能。文中面向铝合金公交车车身结构提出一种连接件的多目标优化设计方法,采用折衷规划法将单目标优化转化为多目标优化,根据优化结果获得兼顾刚度和振动频率要求的公交车连接件拓扑结构,并开展整车强度及刚度分析。结果表明:优化后的连接件质量减少35.79%;整车一阶固有频率提升12.1%;骨架弯曲刚度和扭转刚度分别提升了14.98%和31.32%;4种工况下公交车整体应力值均未超过其材料的许用应力。

Aluminum alloy bus body mostly adopts mechanical connection,and the design quality of connectors is directly related to the comprehensive performance of aluminum alloy bus in terms of stiffness,strength,modal and lightweight.This paper proposes a multi-objective optimization design method for connecting parts for aluminum alloy bus body structure,uses the compromise planning method to transform single-objective optimization into multi-objective optimization,obtains the topology of bus connectors that takes into account stiffness and vibration frequency requirements according to the optimization results,and analyzes the strength and stiffness of the whole vehicle.The results show that the quality of the optimized connection is reduced by 35.79%.The first-order natural frequency of the vehicle is increased by 12.1%.The bending stiffness and torsional stiffness of the skeleton are increased by 14.98%and 31.32%respectively.Under the four working conditions,the overall stress value of the bus doesn’t exceed the allowable stress of its material.