硕士学位毕业论文

硕士研究生：许瑞

指导教师：沈斌 教授 

答辩时间：2013.06

摘要

液压支架是煤矿综采设备的重要组成部分，其主要作用是与采煤机配合，实现采煤的综合机械化，提高采煤效率。为提高综采设备企业的国际市场竞争力，首先要缩短液压支架开发设计时间，并对其尺寸参数进行优化，在保证设计质量的前提下，尽量减少材料，节约成本。立柱是液压支架的主要承载部件之一，在支架正常工作时，立柱一直处于高压受力状态，它的设计合理与否会直接关系到整个液压支架的质量和性能。因此本文选择液压支架立柱作为主要研究对象。

（1）本文在对液压支架做简要介绍的基础上，使用Pro/E软件自带的开发工具Pro/TOOLKIT，结合Visual C++语言，构建了液压支架参数化设计平台。使设计人员只需简单的输入液压支架各零件的尺寸，即可快速得到零件的三维模型。

（2）运用理论力学、材料力学和弹性力学原理对立柱进行静力学理论分析，得出不同工况下，立柱各段的最大挠度、弯矩和应力的计算公式，并进行强度和稳定性校核。然后运用有限元分析软件ANSYS对双伸缩立柱进行有限元分析，通过和理论计算的对比，验证了两种方法的正确性。

（3）在开采具有冲击倾向的煤层或坚硬顶板断裂后迅速沉降时，会产生巨大的冲击，这就要求立柱具有较高的抗冲击能力或对立柱采取适当的保护措施来提高其强度及可靠性。本文通过建立立柱在冲击载荷下的数学模型，得到了冲击载荷下立柱中缸和底缸内液体压力的变化函数，并运用动态显式有限元软件LS-DYNA和光滑粒子流体动力学方法（SPH）对立柱进行冲击载荷下的流固耦合分析，得到了立柱缸体的应力和应变的时间序列。分析结果表明：由于冲击使得缸体内液体压强急剧升高，不仅对立柱自身的安全性造成极大的威胁，同时引起的动载荷对底座和地基造成了很大的冲击力。

（4）立柱结构参数及工作参数的选取，对立柱的动态特性影响很大，如果取值不当，将导致重大的安全事故和经济损失。本文通过最优拉丁超立方取样和有限元仿真实验，构造了冲击载荷下立柱质量、最大应力和动载荷系数的径向基函数代理模型，并使用改进的非支配排序遗传算法对立柱结构进行多目标优化，得到了一组最优解。 

关键词：液压支架，双伸缩立柱，参数化建模，有限元分析，多目标优化

ABSTRACT

Hydraulic support  is an important component of coal mining equipment.  Its main role is to coordinate with the shearer ,   to achieve the comprehensive mechanization of coal mining and improve mining efficiency. To improve the international competitiveness  of  mining equipment’ enterprises,  we must first reduce time of the hydraulic support’ s design , and optimize its dimensions to ensure the quality of design under the premise of minimizing material ,and save cost. Hydraulic support column is one of the main bearing member of hydraulic support.When Hydraulic support works, the column has been in a high stress state all the time. So whether its design is reasonable or not will be directly related to the quality and performance of hydraulic support.

(1)Based on a brief introduction of the Hydraulic support, this paper uses the Pro/E software development tool Pro/TOOLKIT, combined with Visual C + + language constructing Hydraulic support parametric design platform. It allows designers to simply enter the dimensions of the Hydraulic support’s parts, then can quickly get 3D models of the parts.

(2)Using theoretical mechanics, materials mechanics and elasticity mechanics, the paper do the theoretical statics analysis of hydraulic Column,and get the maximum deflection,bending moment and stress calculations of each column’s section in different conditions. Then using the finite element analysis software ANSYS, analysis Double Telescoping. Through comparison with theoretical calculations verify the correctness of the two methods.

(3) With the impact of mining coal seam or a tendency to settle rapidly after breaking hard roof, it will have a huge impact, which requires a high impact resistance column or columns to take appropriate protective measures to improve its strength and reliability. In this paper, by establishing the mathematical model , obtained change functions of the fluid pressure in the  under column and ober column under impact loading .And using the dynamic explicit finite element software LS-DYNA and smoothed particle hydrodynamics method (SPH ) do fluid-structure interaction analysis of the column under impact load, getting the time series of the stress and strain of the cylinder column. The results show that: the impact load makes pressure of the liquid in the cylinder increase rapidly, not only cause a great threat to the safety of the column itself, but also the caused dynamic load has a great impact on the base and foundation.

(4) The parameters of the column structure and operating  have a great influence for the column’s dynamic characteristics.If the value choiced inappropriate, will lead to major security incidents and economic losses. In this paper, by the optimal Latin hypercube sampling and finite element simulation, structure the maximum stress and dynamic load factor’s RBF agent models for the column under impact loading. And use improved non-dominated sorting genetic algorithm for multi-objective optimization of the Double telescopic column, getting a set of optimal solutions.

Key Words: hydraulic support, dual telescopic column, parametric modeling, finite element analysis, multi-objective optimization