大型回转窑筒体的力学分析与计算

【作者】 张波；

【导师】 景作军；

【作者基本信息】 北方工业大学 ， 机械设计与理论， 2012， 硕士

【摘要】 低品位矿产资源将是未来冶炼原料的重要来源之一,然而该类资源具有选矿难度大,直接冶炼处理物料量大,能耗高等特点,要求设备大型化,同时又由于冶金回转窑在高温,腐蚀性高的环境中运转,导致其力学行为非常复杂,因而研究大型回转窑的力学行为,掌握其应力应变规律,具有重要的工程意义。本文完成了年处理120万吨矿石的大型回转窑筒体的主要参数设计与三维几何建模,具体包括回转窑跨度的分布,筒体厚度分布,矩形滚圈截面参数确定。并在梁理论的指导下,完成了回转窑的载荷计算,具体包括筒体载荷计算,各支座处弯矩计算,以及支座反力计算,并对力平衡进行了验证。本文尝试应用薄壳力学去求解回转窑的应力应变,推导了回转窑筒体在法向载荷作用下的位移函数,并在求解位移函数的16个未数知时,建立了回转窑筒体两端的边界条件,这些边界条件包括筒体两端的中面拉压力,中面扭矩,中面弯矩和中面剪力,最后在MATLAB程序下,给出了回转窑筒体在法向均布载荷作用下各向应力、应变的解析解。通过ABAQUS仿真试验结果表明,在薄壳理论指导下求解回转窑筒体的应力、应变是合理的。筒体横向刚度和纵向柔度对回转窑的运转率影响很大,当刚度不足时,会引起耐火砖脱落,而柔度不足时,会因支座不均匀沉陷而引起过大的附加弯曲应力。用薄壳理论求解大型回转窑筒体的应力、应变,打破了过往将回转窑力学问题简化为一维梁模型的假定,将回转窑力学问题回到三维层面来探讨,所求解的回转窑环向应力应变以及轴向应力应变,对优化回转窑的横向刚度和纵向柔度具有实际意义。更多还原

【Abstract】 Low taste of mineral resource will be an important source of future smelting raw materials. However, dressing such resource is very difficult and high energy consumption, which requires large-scale equipment. Metallurgy rotary kiln operates in high temperature and corrosive environment, resulting the mechanical behavior of rotary kiln is very complex. And thus to study the mechanical behaviors and master the relationships between force and distortion rule of rotary kiln is very important in engineering science.The main design parameters and3D geometric modeling of the large-scale rotary kiln which can handle1.2million tons ore per year have been done, including the distribution of the rotary kiln span, cylinder thickness distribution, and rectangular rolling circle cross-session parameters. Under the guidance of the beam theory, the completion of the load calculation of the rotary kiln, including the cylinder load calculation, the moment at each bearing, and the support reaction force calculation.This paper take a bold attempt to apply thin shell theory to solve stress-strain of the rotary kiln, depth derived the displacement function of rotary kiln of the load under the non-simply supported edges, and given a reasonable boundary conditions for16unknowns in solving the displacement function, these boundary conditions including surface pull pressure, surface torque, surface moment and surface shear, and finally export the stress-strain analytical solution of rotary kiln under the uniformly distributed load. ABAQUS simulation results show that the stress and strain is reasonable.Lateral stiffness and vertical flexibility affect the operational efficiency of the rotary kiln. When the stiffness is low will cause firebrick off. And cause additional bending stress when lack of the flexibility. Using shell theory to solve the stress and strain of the large scale rotary kiln is a very valuable attempt. Such attempt break the assumption of one-dimensional beam model, and take the problem back to the three-dimensional level. Through theory get the hoop stress and deformation, and axial stress and deformation. This has very important practical significance for optimization of the lateral stiffness and vertical flexibility of the rotary kiln.更多还原