重型载货汽车车架有限元分析及其优化.pdfVIP

摘 要 摘 要 车架作为重载汽车的承载基体，承受来自汽车部件、货物以及外部载荷的力及力 矩，必须保证其有足够的刚度和强度，深入分析车架的力学性能是车架设计，优化的 基础，同时也是保证整车性能的关键。因此，对车架的研究具有重要意义。 本文以某公司混凝土搅拌车车架为研究对象，以提高车架强度、刚度和可靠性为 目的完成新型车架优化设计。通过在 HyperMesh 中建立车架有限元模型，分别对车 架进行静态、动态有限元计算，获得车架在弯曲、扭转、紧急制动三种工况下的应力 应变参数，以及车架的模态和瞬态响应情况；在车架静、动态承载研究的基础上，使 用基于变密度法的多目标拓扑优化方法对车架实施优化设计，通过修改原有车架模 型，调整相关参数，给出了新型车架的设计方案；通过 RADIOSS 软件对优化后的设 计方案进行仿真验证。 研究成果表明：原有车架虽然在静态工况下危险截面最大应力低于材料许用应 力，但在整体强度上有富余，存在大量可优化空间；在承受瞬态载荷时车架与悬架连 接处存在不合理应力集中，容易出现断裂等安全隐患；根据多目标拓扑优化结果，本 研究提出在车架前端设计一根新横梁和重新布置第一、第二横梁位置。经仿真验证， 新车架各静态、动态指标均有较大幅度提高。 关键词：车架；有限元法；静态分析；瞬态响应；多目标拓扑优化 I 万方数据 摘 要 ABSTRACT The frame as the base of heavy-duty truck bears kinds of forces and moments from the automotive parts, goods, and external load, and must ensure it has sufficient stiffness and strength of frame. Depth analysis of the mechanical properties of the frame is the basic of frame design, optimization and the assurance of vehicle performance. So it will be realistically significant to research the frame. The concrete mixer frame was used as study object to complete the new design of frame that has more strength, stiffness and reliability. To establish a finite element model of frame in Hypermesh, the static and dynamic performance of frame was calculated to get the stress and strain under the condition of bend, torsion and emergency break, model and transient response were also calculated. The multi-objective topology optimization based on the variable density meth