Modeling and Analysis of Transitional Tube with Constant Sectional Area along Derivative Central Route

Firstly,sample square-circular transition tube along straight central route was modeled on CATIA software.The parameters are as follows:let the tube length is L,and the constant cross section area is S,and S=πR2=a2,in which R stands for the circle radius on one end,and a the square side length on the other end;set up the coordinate system with OX axis on the central route in which the origin O is on centroid of the square end and assume the cross section size at x as the square shaped with all four corners filleted in radius r which is proportional to x,that is,the linear slope of r is R/L,thus,both values r and square side length ax can be attained on the constant cross section area assumption.Secondly,some sample polygonal-circular transition tubes along straight,circular and helical central route were implemented similarly.Thirdly,numerical analysis of stress and displacement of these tubes were carried out on MSC/PATRAN software which are important to the distribution of turbulent flow and the layout of these transitional tube structures.     

Enhancement of Heat Transfer in a Tube with Swirl Generators

Influence of strip self-rotating plastic spiral elements inserted in a tube on heat transfer enhancement is studied experimentally. The strip consists of 100 self-rotating spiral elements made of plastic polycarbonate inserted in the inner tube of a concentric tube heat exchanger with a view to generating swirl flow that helps to increase the heat transfer rate of the tube. Cold water flows in the annulus whereas the hot water flows in the inner tube. The obtained experimental data are compared with the data obtained from plain tube .Experimental results confirmed that the use of self-rotating plastic spiral elements leads to higher overall heat transfer coefficient than the plain tube. This technology is not only useful for heat transfer enhancement but also can be used for self cleaning deposition fouling in heat exchanger when the flow velocity is higher than 0.2 m/sec.     

Realization of an automated microassembly task involving micro adhesive bonding

An automated approach is proposed for a microassembly task, which is to insert a 10 μm diameter glass tube into a 12 μm diameter hole in a silicon substrate, and bond them together with ultraviolet （UV） curable adhesive. Two three-degree-of-freedom micromanipulators axe used to move the glass tube and the dispensing needle, respectively. Visual feedback is provided by an optical microscope. The angle of the microscope axis is precisely calibrated using an autofocus strategy. Robust image segmentation method and feature extraction algorithm are developed to obtain the features of the hole, the glass tube and the dispensing needle. Visual servo control is employed to achieve accurate aligning for the tube and the hole. Automated adhesive dispensing is used to bond the glass tube and the silicon substrate together after the insertion. On-line monitoring ensures that the diameter of the adhesive spot is within a desired range. Experimental results demonstrate the effectiveness of the proposed strategy.     

Simulation of Somatotype of Hydraulic Turbine Draft-Tube

Elbow draft-tubes are widely used in largeand medium-sized hydropower stations in many countries.During the application,handling the somatotype of elbow tubes has been found challenging: in order to maintain the designed shape of draft tube and to meet the requirement of construction lofting,the configuration of reinforcing bars and the fabrication of templates,the geometry of elbow tubes has to be accurately calculated to draw engineering graphics.Based on the derived equations in this paper,the motion of elbow tube curve envelope is simulated by using computers,which shows directly the smoothness of the curve and provides dynamic simulation for the study and optimization of the design and construction of elbow draft tubes,along with the front view and bottom view.     

Modular supervisory control for multi-floor manufacturing processes

Due to space availability limitations and high land costs, there is an increasing development of multi-floor manufacturing (MFM) systems in urban and industrial areas. The problem of coordination in a multi-floor manufacturing process, in the Ramadge Wonham framework, is introduced. The manufacturing chain of each floor and the elevator system are modeled in the form of finite deterministic automata. The models of the multi-floor manufacturing process are parametric with respect to the number of floors and the number of manufacturing machines on each floor. The coordination desired performance is formulated in the form of desired regular languages in analytic forms. The languages are realized by appropriate supervisors in the form of finite deterministic automata. The models of the supervisors are also parametric with respect to the number of floors and the number of manufacturing machines on each floor. The total control of the coordination of the multi-floor manufacturing process is accomplished via a modular supervisory control architecture. The complexity of the supervisors as well as the complexity of the total modular supervisory architecture are determined in analytic forms with respect to the number of floors and the number of manufacturing machines on each floor. The special case of a two floor manufacturing process is presented as an illustrative example.     

液晶驱动电路HT 1612及其在蒸汽流量积算器中的应用

The features and the basic operation method of the HT1621 liquid crystal display driving circuit are introduced． With the steam flow to talizer as example the design of relevant hardware and software for the application of HT1621 in liquid crystal display ins truments is described in brief．     

智能计量仪表中掉电重启动的实现方法

The method of imple menting restart after power outagein in struments based on single chip computer is introduced． The requirement of restart and the detection of power outage as well as the flow charts of power outage processing procedure and restart program are described．     

工作流过程定义中的分层结构与正则Petri网

The abstract level problem and the classification of the abstract level problem in the workflow process model are discussed. The formalized problem of the abstract level problem in the process model is researched. The concept and definition of the petri net with end-transition and normal petri net according to the control abstract level problem are put forward and discussed. The equivalence of general Petri Net and general Petri Net is proved by the petri net with priori relationship.     

Information Model for Product Modeling

The Key problems in product modeling for integrated CAD ∥CAM systems are the information structures and representations of products.They are taking more and more important roles in engineering applications.With the investigation on engineering product information and from the viewpoint of industrial process,in this paper,the information models are proposed and the definitions of the framework of product information are given.And then,the integration and the consistence of product information are discussed by introucing the entity and its instance.As a summary,the information structures described in this paper have many advantage and natures helpful in engineering design.     

涟钢30m2和40m2烧结机自动配料控制系统

The burden system of sintering machine and the retrofit of using PLC and host computer to replacet he manual operation are described． The retrofit obtained good result． The compos ition of the automatic burden control system， the selection of PLC and weighing control instrument， control and operation of the system are introduced concretely． Also the functions and features of system software and the anti-interference measures of the system are presented．     

管类钣金结构接口几何信息的分析与提取

在分析国内钣金行业生产需求的基础上,研究管类钣金结构接口的板厚处 理,提出了接口几何信息提取的原理、方法和步骤,从图解、解析建模和基于数值方法的系 统开发等几方面,实现了接口几何信息的精确提取和厚板构件准确的板厚处理,其思想方法 和步骤具有一定的通用性,研究结果对于提高管类钣金结构的产品质量、降低生产成本具有 应用价值。     

基于最短距离法的钢管测厚方法研究

钢管厚度一直是工业生产中的重要待测参数.针对钢管的传统接触式手工测量所带来的低效,高成本等问题,将图像处理技术应用于钢管的厚度测量领域.根据待测钢管的客观情况和所采集到的图像特征,研究了使用基于图像分析处理的技术来实现钢管的厚度测量的问题,并加以实现.最终,获得一定精度的测量结果.     

基于Abaqus的弯管成形数值优化插件开发

为提高弯管成形的数值优化效率,解决小半径弯管生产困难的问题,采用基于Python的Abaqus脚本接口和用户图形界面工具包进行脚本功能及用户界面二次开发,形成专用插件.插件包含弯管成形定义、分析任务提交及成形结果查看等3个模块,为弯管的系列数值实验提供完整、高效且易操作的解决方案.使用此插件进行的数值模拟用时大幅缩短,且所得结果与现场实验吻合良好.     

绕片式翅片管自动化生产线控制系统设计

翅片管是一种新型高效节能的热交换元件,是空气冷却器上最基本、最重要的元件。本文围绕翅片管生产线各个组成部分的结构、功能要求出发,确定控制系统总体设计方案,集成了计算机数控技术、电机驱动技术、PLC控制技术等最新成就,开发出的翅片管生产线,具有设备功能齐全,可靠性高、功能强等显著特点。     

彩管企业制造执行系统的设计与实现

由于各制造企业的管理体系、生产流程相差很大,传统的制造执行系统主要是针对特定企业进行定制式开发,很少考虑通用问题。针对传统MES的不足,提出行业通用MES的建设。通过对彩管业的广泛调查、研究,设计出彩管行业通用MES。在此基础上,将系统成功应用到某彩管企业。实践表明:对彩管企业采用所提出的设计和实现方案效果良好。     

JSG-8型束管火灾监测系统井下布置方案探讨

介绍了JSG-8型束管火灾监测系统的工作原理及结构;针对工作面、采空区煤自燃指标气体采集困难的问题,详细阐述了该系统束管测点在工作面及采空区的布置方案,并指出在工作面进行束管测点布置时需考虑对工作面生产的影响程度。     

基于边缘模式比对的钢管在线视觉测长系统

针对石油钢管测长精度问题，采用二维图像面阵摄像方案，提出边缘模式比对检测算法在亚像素精度级上检测钢管头尾部边缘，设计实现了钢管在线视觉测长系统；该系统具有抗图像噪声、抗图像模糊、抗摄像机抖动、环境适应性强等优点；钢管的测长范围在7～14m，测长误差小于1mm；系统对硬件要求较低，具有很高的性能价格比，并且已经成功地应用到生产现场。     

薄膜在线厚度检测方法及应用

为了提高聚乙烯塑料薄膜质量,生产过程中实时对薄膜厚度进行检测非常重要,介绍一种基于电容式传感器测量原理、实现薄膜厚度在线测量的方法,满足生产过程中对制品进行连续测量监控的要求。同时由于薄膜生产线的工艺特点,生产过程一般采用双层折叠方式,在线检测通常只能测量双层总厚度,提出一种采用计算机软件运算方式将双层测量结果转换为单层厚度的方法,解决实现单层厚度在线测量的难题。     

螺旋缠绕管式换热器传热性能优化与计算程序开发

螺旋缠绕管式换热器作为新型换热设备,与传统换热器相比,更为紧凑的管排列方式,增大了设备单位体积内的传热面积,且流体流动过程更易多流股化,从而提升传热综合效率;对设备的传热特性进行研究并与计算机技术相结合实现性能优化与计算方法改善,对于实际设备设计生产与使用具有重要意义;通过计算流体力学（CFD）方式,对螺旋缠绕管式换热器进行简化计算模型结构工作并开展数值模拟,研究不同管排列方式,相邻管层间距,壳程流速,换热管使用材料在设备换热性能方面的影响情况,得到设备优化结构,实现设备性能提升;选定管内径,管缠绕圈数,壳程流速以及管缠绕半径四个因素及其相对应水平参数开展正交试验,并分析单因素对于绕管式换热器综合传热性能PEC的影响情况及各因素的主次程度;运用Visual Basic语言进行计算程序开发,通过对流体物性参数,管内径,管缠绕圈数,管程数等进行输入并自动计算,实现压降,传热系数,综合性能指数等结果的可视化,提高后期设计工艺计算精度。     

光气合成反应器动态仿真

该文对光气合成管式反应器的动态仿真技术进行了研究.根据物料及焓守恒方程建立了管式反应器的动态机理模型,并根据模型的形式和特点选择了适当的数值计算方法,开发了光气反应器的动态模拟程序模块.模块应用结果表明,达到稳态时的结果能比较真实地反映生产实际情况,动态过程能很好地反映生产的变化趋势,并能完成对非正常工况的模拟.该模型对光气合成反应器动态特性和控制方式的研究以及光气合成相关工艺仿真培训系统软件的开发等都有重要的意义.