液压冲击凿岩系统优化的研究

【作者】 陈红正；

【导师】 徐吉昌； 舒大文；

【作者基本信息】 昆明理工大学 ， 机械制造及其自动化， 2002， 硕士

【摘要】 本论文在冲击凿岩的理论基础上，应用波动力学理论，研究了冲击凿岩系统优化设计中的一些问题。 (1)提出了液压凿岩机优化设计的一种新方法。主要思想是，用运动学特征系数C(回程速度比)作为设计变量。那么根据不同设计要求建立起来的目标函数，均可表示为运动学特征系数C的函数。给出以蓄能器排量最小为设计目标，介绍了如何建立目标函数及其优化问题。 (2)以弹性杆为核心，建立了由四个基本元件构成的凿岩机械力学模型。在此基础上，建立了一元、二元冲击系统的波动力学方程，给出了冲击系统的击入量和效率，分析了冲击系统与工作介质的动态匹配关系。 (3)从弹性体接触定律出发，阐明了冲锤与杆撞击局部变形的线性模型的物理意义。利用VC语言编写电算程序，模拟冲锤与杆撞击产生的应力波。 (4)分析了在给定入射波波长和给定应力波传递特性的情况下能量传递效率最高的应力波形状。对比了最优入射波与通常采用的矩形入射波的传递效率。可以看出其差值相当小。更多还原

【Abstract】 In this paper , based on the theory of percussive drilling , the following optimum design of hydraulic rock drills are studied with the application of wave mechanics.(1) It presents a new method of optimum design for hydraulic rock drills.The main ideal is that the kinematic characteristic coefficient C (the ratio of return velocity) is designated as the design variable. Ihen ,all the objective functions set up according to different design requirements can be expressed as the functions of the kinenatic characteristic coefficient C. The problems concerned with the set-up and optimization of the objectivefunction are discussed, if the minimum oil delivery of accumulators is chosen as the target.(2) Round a elastic rod,this paper establishes a rock drill model which composed of four basic components .Then, this paper establishes wave mechanics equations for impact systems with single element and two elements, Presents the penetraton and efficiency of the impact systems.and analyses the matching relationships under dynamic condition between the impact systems and working media systematically.(3) From the contacting elastomer law, the physical meanings of the linear model of with local deformation in the impact between a hammer and a rod are demonstrated. Then a new program written in VC language is developed and used to simulate the stress wave caused by the impact between the hammer and the rod .(4) The shape of the stress wave with maximum energy transmission efficiency is analysed under these circumstances that duration of the incident wave and the characteristic resistance are given.Then the energy transmission effiency of the optimum incident wave is compared with that obtained from a rectangular incident wave which is usually used.lt is can from be seen that their difference is very small.更多还原