大型直线振动筛动力学分析及侧板拓扑优化布局研究

发布时间：2018-02-16 10:14

本文关键词： 振动筛侧板动力学性能拓扑优化疲劳寿命　出处：《辽宁工程技术大学》2015年硕士论文　论文类型：学位论文

【摘要】：目前振动筛的大型化需求迫切,大型振动筛可以提高生产效率,降低设备费用,提高经济效益。大型化振动筛筛分量增加,结构尺寸变大,对整机及结构部件刚度、强度要求增加。大型振动筛整机及其结构部件的动力学性能影响着其工作的可靠性、稳定性,对振动筛整机及其结构部件进行动力学性能分析及结构的优化具有重要意义。本文主要采用拓扑优化方法对振动筛进行结构优化设计。在给定条件下,确定结构内空洞的位置和数量,各构件连接方式等拓扑形式,使得结构将外载荷传递到支座上时,结构的某种指标达到最优的过程,称为拓扑优化。以ZK3050型大型直线振动筛为研究对象。首先建立了振动筛力学模型,进行了运动学分析,确定振动筛的主要工艺参数。应用ANSYS软件,系统建立振动筛整机及其各主要部件的有限元分析模型。应用ANSYS对振动筛整机和主要部件(侧板、横梁、入料梁、出料梁、弹簧支撑等)进行了模态分析和谐响应分析,得到整机及各部件的前几阶固有频率及振型、动应力和变形结果。振动筛整机及侧板的前几阶固有频率均有效避开工作频率,横梁、入料梁、出料梁、弹簧支撑装置各阶固频均远大于工作频率；整机及主要部件的动应力和变形均在材料许用范围内。侧板的最大动应力远远小于材料的许用应力,安全系数较大。通过对多家选煤厂的走访调研,调研结果显示侧板极少出现裂纹、变形等破坏失效问题,符合动力学分析的结果。考虑到传统设计侧板存在材料富余,对ZK3050型大型直线振动筛侧板进行轻型结构改进。基于变密度法的拓扑优化理论,对侧板加强肋的拓扑优化优化布局设计,建立以刚度最大为目标函数的侧板加强肋布局的拓扑优化数学模型,根据拓扑优化分析所得材料密度分布云图进行加强肋的布局,得到侧板新的结构方案。优化后侧板结构与原侧板结构相比,厚度减小2mm,总重量减小32Kg,参振质量降低,节省了材料和能耗。对优化后侧板进行模态分析、谐响应分析以及疲劳寿命分析结果表明：优化后侧板各低阶固有频率相比优化前有普遍提高,并有效避开工作频率;最大动应力、最大变形均在材料许用范围内；疲劳寿命达到使用要求。
[Abstract]:At present, the demand for large scale vibrating screen is urgent. Large vibrating screen can improve production efficiency, reduce equipment cost and increase economic benefit. The dynamic performance of the large vibrating screen and its structural parts affects the reliability and stability of its work. It is of great significance to analyze the dynamic performance of the vibrating screen and its structural components and to optimize the structure. In this paper, the topology optimization method is used to optimize the structure of the vibrating screen. The location and number of holes in the structure and the connection modes of each member are determined, so that when the external load is transferred to the support, a certain index of the structure can reach the optimal process. It is called topological optimization. Taking ZK3050 type large linear vibrating screen as the research object, the mechanical model of vibrating screen is established, the kinematics analysis is carried out, and the main technological parameters of vibrating screen are determined. ANSYS software is used. The finite element analysis model of the vibrating screen machine and its main components is established. The modal analysis and harmonic response analysis of the vibrating screen machine and its main components (side plate, cross beam, feed beam, discharge beam, spring support, etc.) are carried out by using ANSYS. The results of the first natural frequencies and modes, dynamic stress and deformation of the whole machine and its components are obtained. The first natural frequencies of the shaker and the side plate are effectively avoided from the working frequency, the cross beam, the feed beam, and the discharge beam. The dynamic stress and deformation of the whole machine and its main components are within the allowable range of materials. The maximum dynamic stress of the side plate is much smaller than the allowable stress of the material. The safety factor is relatively high. Through the investigation and investigation of many coal preparation plants, the results show that there are few cracks, deformation and other failure problems in the side plate, which accords with the result of dynamic analysis. Considering the surplus of materials in the traditional design side plate, The light weight structure of the side plate of ZK3050 type large linear vibrating screen is improved. Based on the topology optimization theory of variable density method, the topology optimization layout design of the side plate stiffener is optimized. A topology optimization mathematical model of stiffener layout with maximum stiffness as objective function is established, and the distribution of stiffened ribs is carried out according to the density distribution cloud diagram of material obtained by topological optimization analysis. A new side plate structure scheme is obtained. Compared with the original side plate structure, the optimized side plate structure reduces the thickness by 2 mm, the total weight reduces by 32 kg, the damping mass decreases, and the material and energy consumption are saved. The modal analysis of the optimized side plate is carried out. The results of harmonic response analysis and fatigue life analysis show that the low-order natural frequencies of the optimized side plate are generally higher than those before optimization, and the working frequency is avoided effectively, the maximum dynamic stress and the maximum deformation are within the allowable range of the material. Fatigue life up to service requirements.
【学位授予单位】：辽宁工程技术大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TH237.6

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