【作者】 王真；

【导师】 赵章焰；

【作者基本信息】 武汉理工大学 ， 机械设计及理论， 2003， 硕士

【摘要】 起重机臂架结构是臂架式类型起重机的重要承载部件之一，其力学性能对整机的正常运转有直接影响，故障率较高。目前在臂架结构的设计和故障诊断中有以下两方面的问题有待解决：1)目前仅是对臂架结构在工作状态下的最大和最小幅度进行结构分析，而起重机在最大到最小幅度的整个变幅过程中，应力和位移等力学参量均难以知晓，关键由于这项工作在设计和验算中是很难或根本无法实现，因此无法全面了解臂架结构在整个变幅运动中的工作状态；2)起升机构起制动时对臂架结构产生强烈的冲击动载荷，其动态响应如何?针对以上两个问题，本论文以单臂架起重机臂架结构为研究对象，以有限元法和机械动力学为理论基础和分析手段，运用参数化技术和有限元分析软件ANSYS对单臂架结构的变幅运动进行了运动数值仿真，研究了单臂架的动态特性和臂架在起吊时的动力学响应，并采用Visual C++ 6.0开发了相应的数值运动和动力仿真软件。主要研究工作如下： 1)用ANSYS的内部命令和APDL语言以及参数化技术建立了单臂架结构的有限元参数化模型。它使得有限元分析过程中对模型的修改以及再次计算很方便、快捷，而且不容易出错。 2)用建立好的有限元参数化模型和ANSYS的内部命令编写了臂架结构变幅运动数值仿真的命令流文件(即log文件)，具体实现了仿真，获得了仿真动画和仿真数据曲线，经分析得出了有参考价值的结论。 3)研究了臂架的动态特性。结合有限元参数化模型编写了模态分析的命令流文件，该模态分析可以是变幅过程中任意幅度的模态分析。提取了前几阶固有频率、主振型及其振型图，并对结果进行了分析。 4)对臂架在货物突然起吊受到动载荷的情况进行了瞬态分析。结合有限元参数化模型编写了瞬态分析的命令流文件，该瞬态分析同样可以实现变幅过程中任意幅度的瞬态分析。获得了臂架突然起吊的瞬态动力响应，包括动应力、动位移响应仿真云图和典型节点的动应力时间历程曲线，并对结果进行了分析。 5)有效地运用Windows编程技术、Visual C++软件对臂架的运动数值仿真和动力学分析进行了封装。独立开发了单臂架变幅运动和动力数值仿真软件，该软件界面友好，操作简便、实用。更多还原

【Abstract】 Jib metal structure is one kind of the important load-carrying structure of jib crane whose mechanical capability effect the whole machine’s running directly and has higher fault rate. At present, on the designing and fault diagnosing of jib structure, there are two fellow problems under solution: 1) Currently, the analyzing of jib structure is only focus on mint and max-range of luffing motion, but during whole luffing process, structure’s stress and displacement are difficult to know because the relevant work is and even can’t be realized. As a result, jib’s working state during whole luffing isn’t learned fully. 2) How about dynamic responses of jib structure while load is lifted at a sudden ? Surrounding the above problems, based on the finite element method (FEM) and mechanic vibration theory and using parameterized method and the FEM simulation software-ANSYS, this dissertation studies the numerical simulation of the single-jib’s luffing motion and it’s dynamic characters and responses while load lifting suddenly and develops a relevant jib kinematics and dynamics numerical simulation software. The main research contents and results of the dissertation are as fellows:1) To build a jib structure’s parameterized FEM model using ANSYS internal command桝PDL and parameterized method. It is conveniently and quickly to modify and recalculate the model in FEM analyzing.2) To realize the luffing numerical simulation. The simulation animation and curves acquired from the simulation have practical engineering value.3) To study the jib structure’s dynamic characters. To program a command stream file (*.log) that is available to any luffing location, gain the several former natural frequency and mode shapes, and finally analyze the results.4) To study the dynamic respond while load lifting suddenly. To program a command file of transient analyze that is also available to any luffing location, obtain the dynamic response results including simulation nephograms of dynamics stress and displacement and curve of dynamic stress of representative nodes.5) To use the Windows message mechanism and Visual C++ in order to pack up the above simulation results. To develop a software of single-jib structure’s kinematics and dynamic numerical simulation whose interface is friend and convenient.更多还原