圆波导管壁电流分布图仿真

基于圆波导的场结构和理想导体边界条件,给出管壁电流分布表达式,然后借助MATLAB语言编程,对圆波导中多种波模的管壁电流分布进行仿真．根据仿真图,容易看出针对横电波最易开缝区为沿φ方向在φ=π／2,3π／2附近,横磁波管壁最易开缝区为沿z纵轴方向也在φ=π／2,3π／2附近．管壁电流分布图仿真对开发规则金属波导图形仿真计算器也很有帮助．     

A state space solution for the bending problem of thick laminated piezoelectric open cylindrical shells

Based on the theories of three-dimensional elasticity and piezoelectricity, and by assuming appropriate boundary functions, we established a state equation of piezoelectric cylindrical shells. By using the transfer matrix method, we presented an analytical solution that satisfies all the arbitrary boundary conditions at boundary edges, as well as on upper and bottom surfaces. Our solution takes into account all the independent elastic and piezoelectric constants for a piezoelectric orthotropy, and satisfies continuity conditions between plies of the laminates. The principle of the present method and corresponding results can be widely used in many engineering fields and be applied to assess the effectiveness of various approximate and numerical models.     

非均匀柱面波的复射线束展开

用鞍点法导出了非均匀桂面波的复射线束展开系数公式，所得结果可用于研究非均匀柱面波在复杂环境中的传播、散射等问题。     

108 m×90 m柱面网壳整体提升施工方法

本文介绍河南省鸭河口电厂干煤棚柱面网壳的施工方法———"折叠展开式"整体提升施工技术.文中详细阐述了这项施工技术的基本思想、关键技术、施工过程和效益分析.这项新技术在国内尚属首次采用,应用于亚洲最大跨柱面网壳的施工中并取得了圆满的成功,证明了这项新技术的正确性和实用性.     

计算紧半代数集的同调方法

提出一个关于计算紧半代数集构成排列的0维Betti-数和1维Betti-数的算法.这个算法的复杂度为单指数复杂度.     

Reaction thrust characteristics of high-pressure submerged water jet of cylinder nozzles

The shapes and geometrical parameters of nozzles are key factors for fluidics. The relationship among the reaction thrust, flow rate pressure, diameter do and length L of a cylinder nozzle is analyzed theoretically. The simulation of the flow field characteristics was conducted via the FLUENT computational fluid dynamics package. Effects of the inlet conditions and the nozzle dimensions on the reaction thrust of a water jet were addressed particularly. The reaction thrust experiments were performed on a custom-designed test apparatus. The experimental results reveal that a） the nozzle diameter and the inlet conditions exert great influence on the water jet reaction thrust; and b） for L≤4d0, where the nozzle is treated as a thin plate-orifice, the reaction thrust is independent of nozzle length; for L〉4d0, where the nozzle is treated as a long orifice, the reaction thrust can reach maximum under the condition of a certain flow rate. These findings lay a theoretical foundation for the design of nozzles and have significant value, especially for the future development of high-oressure water-let orooulsion technology.     

应用基矢量的物质导数公式简化流体运动微分方程式的推导

推导柱坐标系及球坐标系下流体运动微分方程组通常采用的方法是根据矢量形式的运动微分方程式,利用物质导数的基本公式和正交曲线坐标系各基矢量的偏导数公式来进行,推导过程相当繁琐,尤其在教学过程中,在课堂内完成上述具体推导过程几乎是不可能的。为了寻找一种简捷的推导方法,本文依据基矢量物质导数的基本公式,计算得出了柱坐标系及球坐标系下的基矢量物质导数公式,并将它们分别应用于柱坐标系及球坐标系下的流体运动微分方程组的推导过程中。结果表明:如果将柱坐标系及球坐标系下基矢量的物质导数公式作为基本公式使用,则可以使上述坐标系下流体运动微分方程组的推导过程得到很大程度的简化。     

圆柱齿轮传动最少齿数的分析

阐述圆柱齿轮根切的概念及避免根切的方法,给出用范成法加工时齿条形刀具和齿轮形刀具不发生根切的最少齿数,并分析重合度对最少齿数的影响,得出两种情况下的最少齿数。     

锥形漏斗自动送销机构

介绍一种自动送销机构,可以根据生产的需要,将大量杂乱无序的圆柱销按一定的顺序和一定的频率送到加工位置,并能适应多种长度规格的圆柱销的传送。     

均匀带电长圆柱面上任一点场强的计算

均匀带电长圆柱面内、外任一点的场强可由高斯定理很快求出，但长圆柱面上任一点的场强却未被涉及，本文利用场强叠加原理对此作一分析。