轿车双轴撕碎机刀盘拓扑优化设计

发布时间：2018-05-15 09:03

本文选题：拓扑优化 + 固体各向同性微结构材料惩罚模型　；参考：《天津科技大学》2017年硕士论文

【摘要】：随着废旧轿车数量的增加,处理废旧轿车成为亟待解决的问题。废旧轿车的破碎主要使用撕碎机,而现有撕碎机大都存在笨重,撕碎效率低,能耗大以及容易出现疲劳损伤等问题。刀盘作为撕碎机的关键部件,其结构直接决定了撕碎机的撕碎效率、能耗和寿命,对刀盘进行轻量化设计非常必要。本论文以撕碎机刀盘为研究对象,研究大型复杂件的拓扑优化方法,并进行撕碎机刀盘轻量化设计。轻量化设计主要依靠拓扑优化算法,目前常用的拓扑优化算法有基于变密度理论的固体各向同性微结构材料惩罚模型法(Solid Isotropic Microstructur es with Penalization, SIMP)以及双向渐进法(Bi-Directional Evolutionary Structural Optimization,BESO)等。其中SIMP方法程序实现简单,计算效率高,但是这种方法的拓扑优化结果不能为之后的设计提供刚度最大的拓扑构型。BESO方法能够得到刚度最大的拓扑构型,但是对于复杂结构,这种方法计算效率低,且拓扑优化结果依赖于网格质量。单独使用这两种算法均无法高效地获得刀盘的拓扑构型。本论文利用SIMP算法找出体积百分数与柔度之间的数学关系,得出体积百分数的约束方程,并将其应用于BESO优化算法中,从而提高了优化效率和优化质量。本论文对轿车双轴撕碎机进行了机械设计,利用ABAQUS软件对撕碎机撕碎过程进行动态仿真,并利用仿真结果对刀盘加载,利用改善后拓扑优化算法对撕碎机刀盘进行拓扑优化,根据拓扑优化重新设计出两种新的刀盘结构,优化刀盘的过程编写为Python程序,得出合理的刀盘构型并利用力学实验验证该结构的合理性,通过3D-DI C实验得出带孔的刀盘结构应变最小,结构最稳定。本论文得出了体积百分数约束方程,改善了 BESO优化算法,采用该方法优化出的刀盘结构,使得撕碎机主轴应力状态得到改善,最大综合应力减少50.4MPa,通过改变刀盘的排布发现螺旋状排布刀盘时撕碎机的破碎效果更好,破碎力是刀盘直线排布时的3.4倍。
[Abstract]:With the increase of the number of used cars, the disposal of used cars becomes an urgent problem to be solved. The shredder is mainly used in the crushing of used cars, but most of the existing shredders are heavy, low efficiency, high energy consumption and easy to appear fatigue damage and so on. As the key component of shredder, its structure directly determines the shredder's tearing efficiency, energy consumption and service life, so it is necessary to design the cutter head lightweight. In this paper, the shredder cutter head is taken as the research object, the topology optimization method of the large complex parts is studied, and the lightweight design of the shredder cutter head is carried out. The light weight design mainly relies on topology optimization algorithm. At present, the commonly used topology optimization algorithms are solid Isotropic Microstructur es with Penalization, SIMP) based on variable density theory and Bi-Directional Evolutionary Structural Optimization method (BESOs). The program of SIMP method is simple to realize and the calculation efficiency is high. However, the topology optimization result of this method can not provide the maximum stiffness topological configuration for the later design, but for the complex structure, the topological configuration of the maximum stiffness can be obtained. The computational efficiency of this method is low, and the topology optimization results depend on the mesh quality. The topology configuration of the cutter head can not be obtained efficiently by using these two algorithms alone. In this paper, SIMP algorithm is used to find out the mathematical relationship between volume percentage and flexibility, and the constraint equation of volume percentage is obtained, and it is applied to BESO optimization algorithm to improve the optimization efficiency and quality. In this paper, the mechanical design of car two-axis shredder is carried out. The shredder is dynamically simulated by ABAQUS software, and the cutter head is loaded by simulation results. The improved topology optimization algorithm is used to optimize the topology of shredder cutter. According to the topology optimization, two new cutter head structures are redesigned, and the process of optimizing the cutter head is programmed as Python program. The reasonable cutter head configuration is obtained and the rationality of the structure is verified by mechanical experiments. The 3D-DI C experiment shows that the structure of the cutter with holes has the minimum strain and the most stable structure. In this paper, the volume percent constraint equation is obtained, and the BESO optimization algorithm is improved. The structure of the cutter head is optimized by this method, and the stress state of the main shaft of the shredder is improved. The maximum comprehensive stress is reduced by 50.4 MPa. By changing the arrangement of the cutter head, it is found that the shredder has a better crushing effect when the spiral arrangement cutter is arranged, and the crushing force is 3.4 times as much as that when the cutter head is arranged in a straight line.
【学位授予单位】：天津科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X734.2;TH122

【参考文献】