螺旋桨伸张轮廓参数化绘制程序的设计

介绍了基于AutoCAD VBA螺旋桨伸张轮廓的参数化绘制方法,包括图样绘图环境的设计、螺旋桨伸张轮廓的计算与绘制,以及程序菜单的设计和程序代码的自动加载等,列举了用VBA编写的相关程序。     

基于NAPA的螺旋桨几何造型和图形生成方法研究

螺旋桨设计是船舶设计中重要的组成部分之一．基于船舶设计NAPA软件平台,使用NAPA自带的NAPA BASIC语言,利用坐标变换方法,根据螺旋桨桨叶的伸张轮廓和叶切面形状,得到了桨叶几何造型所需的三维坐标值,同时研究了桨叶二维图形的生成方法,从而有效地将船舶设计软件与螺旋桨的几何造型紧密结合起来,节省了大量的人力物力,提高了工作效率,推动了计算机技术在螺旋桨设计领域的应用,为船用螺旋桨的精确和高效绘图寻求了一条新途径．     

螺旋桨绘图数值计算程序

螺旋桨设计完成后，绘图时要进行许多计算，并且要用作日方法求出各相对半径处随边和导边的长度才能作图。本程序通过计算机，根据需要可计算出B型、JB（经验）型、MAU及AU型、Ka型四种桨中的任何一种桨的伸张轮廓、展开轮廓和投影轮廓的x、y、z三个坐标，并可计算出各相对半径处叶剖面各部位的厚度。在计算机上仅需几分钟即可打印出所需数据。     

现代船用螺旋桨设计应用程序研究

通过建立在现代螺旋桨数值升方面理论一涡格法基础上的计算程序的数值试验，对照实验数据，改进了程序计算结果的准确性。应用程序设计了螺旋桨，并进行了模型试验，螺旋桨的推进和空泡性能符合设计要求，进一步证明了设计程序的实用性和可靠性。为了方便应用程序，采用混合编程形式，构成现代螺旋桨实用程序包。该程序包可以完成螺旋桨理论设计、水动力性能计算、最佳侧斜选择和绘制螺旋桨图纸等工作。     

船用螺旋桨参数化绘图程序设计

根据螺旋桨总图的基本投影原理，提出了进行螺旋桨二维参数化绘图程序设计的方法，作为实例，作者在Auto CAD2000环境下用VBA语言编制了MAU型螺旋桨的参数化绘图程序。     

某内河拖船螺旋桨设计

螺旋桨设计是整个船舶设计的重要组成部分。影响螺旋桨推进性能的因素很多,在本设计过程中主要对螺旋桨的直径、螺距比、盘面比、桨叶轮廓形状等因素进行研究,并结合在工作中积累的经验,设计一艘性能较好的内河A级拖船的螺旋桨。     

导管参数对导管螺旋桨水动力性能影响研究

对42 m拖网渔船设计了导管螺旋桨,利用FLUENT软件计算其敞水水动力性能。在保持螺旋桨形状不变的情况下,改变导管的长径比、收缩系数和伸张系数三个形状参数,分别计算并比较它们的敞水水动力性能,进而研究导管参数对整个推进器推进效果的影响规律。     

导管空气螺旋性能计算与绘图的一体化实现

在Excel中编程实现了导管空气螺旋桨的性能计算,使得计算过程更加直观可视,并将计算结果较快转化形成导管桨性能计算书中的表格形式。在AutoCAD中编制了LISP程序,利用Excel中生成的剖面型值,较为方便的绘制桨叶图,并自动加密剖面轮廓线控制点以形成CATIA中建模所需数据文件。在CATIA中通过二次开发,实现了桨叶三维模型的自动绘制,该模型不仅可用于整艇的三维建模,亦可用作CFD计算的输入模型。对设计过的气垫船导管空气螺旋桨进行汇总,形成了设计数据库。     

面向CFD的螺旋桨逆向三维曲面建模方法

针对螺旋桨三维外形的曲面特征,结合螺旋桨二维图绘制方法和CATIA中曲面逆向设计方法,根据螺旋桨二维投影轮廓图,逆向投影进行螺旋桨三维建模,生成面向CFD的三维模型,进行水动力数值分析,实现螺旋桨的优化设计。     

水空两用对转螺旋桨快速设计方法

螺旋桨是目前水空两用装备动力推进的主要形式,能使装备多次完成水/空运动的切换。为快速得到最大效率时螺旋桨的几何特性,为螺旋桨详细设计提供数据输入,本文基于动量叶素理论,并通过与翼型升阻力系数快速计算的XFOIL程序进行融合,开发出水空两用对转螺旋桨快速设计程序。通过与文献结果对比及进一步分析,该螺旋桨快速设计程序可靠,最大相对误差不超3%。该程序可为水空两用对转螺旋桨详细设计提供预先输入,加快设计进程。另外,根据设计程序计算结果以及单排桨与对转桨间的效率关系,开展对转螺旋桨风洞试验,效率可达75%。该快速设计方法为后续一系列对转螺旋桨试验研究做准备,并提供生产加工相关参数。     

Errata

正In the paper"Influence of Fouling Assemblage on the Corrosion Behaviour of Mild Steel in the Coastal Waters of The Gulf of Mannar,India"in Vol.12,No.4,Page:509,References were lost,and the two authors’biographies were identical.The correct text is shown below.We apologize to the authors and our readers for any inconvenience caused by the errors.     

Journal of Marine Science and Application 2014 Sum. Contents

正~~     

第34届海洋、离岸及极地工程国际会议(英文)

正St.John's,Newfoundland,Canada,May 31-June 5,2015 OMAE2015 is the ideal forum for researchers,engineers,managers,technicians and students from the scientific and industrial communities from around the world to: meet and present advances in technology and its scientific support;     

联合作战计划和执行系统

全球指挥控制系统(GCCS)实施当前美国海军网络中心战信息基础设施的联合计划网络。联合作战计划和执行系统(JOPES)支持GCCS实现联合计划。JOPES有两类计划：时间不限的精密预案计划生成作战计划、方案计划或职能计划；时间敏感的危机行动计划生成作战命令或战役方案。前者在和平时期创建的作战计划是后者的计划基础，加速应付危机的能力。     

Eastbound or westbound ?

In terms of equal sailing distances, where is the inflexion when ships depart from ports in the Asian Continent to New York via Suez and/or Panama？
The answer is China South Port Group （Hong Kong, Shenzhen and Guangzhou）.     

Recent progress on wave induced loading measurements in warships

Recent measurements of wave induced hull strain and flexure in RN warships are presented together with the derivation of the current design criteria for extreme hull girder bending loads. The history of the development of the shipboard instrumentation used is given and recent developments to improve the quality and ease of analysis of the data are described. An unexpectedly high transverse asymmetry in the longitudinal strains measured in destroyers is shown to be the result of a combination of vertical and lateral bending in oblique seas. Finally recent theoretical comparisons between the loading of Deep-Vee hulls and conventional UK rounded bilge hulls are presented which demonstrate the higher loading experienced by this type of hull form.     

桥梁防撞设施物理模型试验

物理模型试验是预报防撞设施所受撞击力及优化设计方案的主要方法之一。结合杭州湾大桥柔性防撞设施及东海大桥独立式防撞体设计方案,阐述了船—防撞体撞击试验的基本原理、方法、试验方案及相关试验结果。提出了柔性防撞系统的优化方案。试验结果表明,该方案经济有效,可供预报类似桥梁防撞设施撞击力时参考。     

印尼某电厂码头水工建筑物设计

印尼某电厂项目码头水工建筑物包括码头、防波堤和护岸等主要组成部分。在该项目水工建筑物的设计过程中,综合考虑当地的自然条件、施工能力和材料来源等因素,不断优化结构选型和结构断面。根据不同使用要求,护岸分别采用直立式和斜坡式2种结构型式,推荐的设计方案节省投资、施工方便,可供同类工程设计参考。     

Impact of regulation on the performances of long-distance transport services: A comparison of the different approaches in Sweden and Norway

Despite the many socio-economic similarities between Sweden and Norway, differences in jurisdiction, organisation, cooperation, and financing of long-distance passenger train and coach services have led to the development of four distinctively different ways of serving the markets. This paper describes how the train and coach markets have developed in the two countries, with emphasis on regulatory and industrial structure and a couple of performance variables.Looking at passenger rail, both countries separated infrastructure from operation over a decade ago. However, while Norwegian rail is characterised by an almost monopoly supplier, rail services in Sweden are partly decentralised to the responsibility of county authorities and are widely subjected to competitive tendering. The rest of the network is about to be opened up for on-the-track competition. Swedish Rail (SJ) has spent the last decades consolidating its core business (passenger rail) and sold out its other businesses. In contrast, the Norwegian state rail (NSB) has expanded its business to become a major bus operator and property owner, with extensions also into the Swedish market.The coach industry was more recently deregulated in both countries. The Swedish coach market is dominated by privately owned companies operating services to and from Stockholm. In Norway, state-owned NSB is a major coach operator on medium distance routes, and is also the largest partner of Nor-Way Bussekspress which totally dominates long-distance coach services. Further, the Norwegian coach market is characterised by cross-ownership and cooperation which has enabled an extensive route network which covers most of Norway.We find distinct differences in achievements in the two modes and in the two countries. Swedish rail services have succeeded in winning market shares and in renewing and developing both infrastructure and service levels to a greater extent than the Norwegian model. On the other hand, the Norwegian coach market seems to be more developed and efficient compared to its Swedish counterpart.The paper concludes with a discussion on the possible links between the different approaches and the performance observed, with the aim to stimulate further and more detailed research on some important issues.     

开放式数据挖掘系统模型

目前国内已经出现了少量的数据挖掘相关产品。国内数据挖掘软件无论从数量还是质量上比较，都与国外软件存在着较大的差距。随着数据仓库技术的普及，数据挖掘应用的需求越来越强烈，如何缩短这种差距，研发数据挖掘软件产品成为国内业界的一个重要问题。通过引用目前国际通用数据挖掘标准技术来构建开放式的数据挖掘系统模型，该系统模型从可扩展性、可重用性、易用性等方面得到了加强。