低速重载纯电动车车架多学科优化设计

Multidisciplinary optimization design of frame for low-speed and heavy-duty battery electric vehicle

纯电动井下运输车是一种低速、重载及零排放的人员运输车辆,其车架采用非承载式结构,有利于提高车架的刚度和强度。但是与承载式车身相比其质量有所增加,影响了整车的续驶里程。为了实现车架轻量化,并保证车架在多种行驶工况下具有足够的强度和刚度以及良好的动态特性,采用多学科优化设计方法,研究了纯电动井下运输车轻量化车架的结构设计问题。为了更准确求解车架所承受的载荷,建立了一种刚柔耦合的车架模型。相比传统方法,该模型将悬架系统和副车架都考虑在车架的分析模型中,能更好地反映悬架系统中弹簧、减振器及导向机构对车架传力路径和传力大小的影响。所研究的整车行驶工况包括满载弯曲、极限扭转和紧急制动转弯。多学科优化设计结果显示,在满足强度和刚度要求,且保持良好动态特性的前提下,车架质量减轻了5.1%,实现了轻量化。

Battery electric underground transportation vehicle is a kind of low-speed,heavy-duty and zero-emission personnel carrier.Its frame is of non-bearing structure,good for improving the rigidity and strength of the frame.However,it is heavier than load-bearing body,affecting the vehicle’s driving range.To lighten the frame and ensure sufficient strength,rigidity and good dynamic characteristics of the frame under various driving conditions,multidisciplinary optimization design method is used to study structural design problems of light-weight frame for battery electric underground transportation vehicle.In addition,a rigid-flexible coupling frame model is established to calculate the precise load on the frame.Compared with traditional methods,the model includes both the suspension system and sub-frame in the analysis model of the frame,thus better reflecting the influence of spring,shock absorber and guide mechanism in the suspension system on force transmission path and magnitude of force transmission.The study is conducted under driving conditions including full load bending,ultimate torsion and emergency brake turning.The result of multidisciplinary optimization design shows that at the required strength,rigidity and good dynamic characteristics,the total mass of the frame is reduced by 5.1%to realize lightweight structure design.