船用齿轮设计技术的发展趋势

船用大功率齿轮传动的突出特点是高速、重载和低噪声。通过对船用齿轮传动装置的主要传动方式介绍和应用分析,表明船用齿轮传动装置技术正向着高承栽、高可靠性、安静型、多种传动形式及小型化的方向发展。文中讨论了国内外齿轮设计技术的热点问题。指出,船用齿轮设计的关键技术是多机多轴联合交叉传动装置设计技术、传动装置高功率密度设计技术、振动及噪声综合控制技术和新型传动元部件动态设计技术。     

船用柴油机振动噪声性能标准分析

针对船用柴油机振动噪声指标越来越受到重视,而这些指标的衡准仍然存在不规范、不系统甚至概念错误的现状,对现有相关的国家和行业标准进行了系统梳理。基于性能评价需求及工程实践,比较了不同指标、不同标准之间的差异和存在的问题,指出并纠正了一些概念和常规理解的差错;着重对相关的测试方法、限值和评价准则进行了深入研究,明晰了各性能指标标准之间的逻辑关系和技术脉络,提出了现有标准要改进和完善之处;给出了这些标准在当前工程应用中的取舍建议,为船用柴油机振动噪声标准体系的建设和进一步完善提供了依据。     

柴油机排气噪声的有源噪声控制

近年来，已经发展了有源噪声控制技术，以降低低频率的噪声。为了将该技术应用于船用柴油机，在882kW／900min-1柴油机上，对管道内置式有源噪声控制（ANC）消声器进行了试验。在200Hz以下的较低频率范围内．排气噪声频谱的峰伍最大降低了35dB。虽然排气温度在300℃左右，但由于采用引射作用的冷却系统，与室温相比，消声器的温升还是抑制在8．3℃内。由此证明它具有足够性能，管道内正式ANC消声器可适用于船用柴油机。     

柴油机排气噪声有源控制的试验研究

尝试利用自适应有源噪声控制技术对４－８５柴油机低频噪声进行空间 消声,取得了一定的消声效果。首先对４－８５柴油机排气噪声频谱进行了分析,然后提出了针对此低频排气噪声应用有源噪声控制技术的可能性。其次讨论了妨碍应用有源噪声控制技术的三大困难,并找出了解决方法。引入次级声场的理论推导并完成了引入次级声场装置的设计、制造。通过对排气噪声信号与排气管上不同位置振动信号的相干性分析,选取参考输入信号,提出了采用自适应有源噪声控制技术,为试验提出了依据,对系统进行了建模并编程,对试验结果了记录并分析。     

MAN与Sulzer柴油机电控燃油系统分析

采用电子控制的智能柴油机在提高柴油机动力性能、经济性能以及排放性能等方面具有优越性,电子控制技术已成为衡量柴油机先进程度的重要标志之一.本文以船用电子控制柴油机为研究对象,分析了当前世界上两大船用柴油机制造公司低速大功率柴油机电控燃油喷射系统的原理和性能特点.     

大功率船用柴油机球铁曲轴的性能研究

我们对大功率船用柴油机球墨铸铁曲轴结构设计、滚压工艺等性能进行了研究,根据球铁曲轴的疲劳性能、CAE分析强度、扭振性能提出相应的评定指标,为大功率船用柴油机球铁曲轴的设计和分析提供了参考。     

在开发下一代柴油机的征途中

<正> 在回答记者提出的什么是新设计柴油机的关键技术要求时,Yanmar柴油机有限公司研究与开发部总经理Hamada认为:燃烧、噪声和振动是关键问题。燃烧技术对柴油机性能和排放两个方面所有工作特性有影响。通过多年用自行开发的喷油技术而进行的理论研究,Yanmar公司已发展形成了自己的燃烧技术。至于噪声和振动,这是研制各种不     

N485Ca高速船用柴油机的开发与研制

主要介绍了N485Ca船用柴油机的结构设计及性能开发的情况,并经试验验证该发动机的排放、噪声、机械振动等指标均符合国家或行业标准的要求。     

D683系列船用柴油机的研制开发

D683系列船用柴油机是在D6114车用型柴油机基础上,借鉴国际上九十年代中期先进船用柴油机的设计经验,由上海柴油机股份有限公司研制开发的新一代高速、轻型、低排放、节能型船用柴油机。功率范围为154～205kW,主要用于高速船艇的主机动力,也可用于舰船的辅机、发电机组等。着重介绍了该系列船用柴油机的性能研究、设计结构和研制开发的情况。     

数字化设计技术在船用柴油机设计中的应用

重点开展了船用柴油机数字化设计关键技术研究,主要包括:柴油机数字化定义、典型关重件参数化设计、零部件可重用模型、柴油机功能化数字样机、燃烧系统多学科优化、柴油机数字化装配等。形成船用柴油机三维数字化设计能力,从而缩短柴油机典型关重件研发周期。     

过热器再热器爆漏事故的原因分析及对策

过热器、再热器爆漏事故严重影响了锅炉机组的安全性和经济性,而造成过热器、再热器爆漏事故的主要因素有超温爆管、磨损、高温腐蚀、热疲劳、质量失控等。通过对这些因素的主要原因和爆口特征的分析,提出了一些过热器、再热器爆漏事故的防治措施。     

具有智能化特征的安全稳定分析与控制决策技术

安全稳定预警与控制辅助决策是智能电网调度技术支持系统不可缺少的应用类功能。在分析安全稳定分析与控制决策计算工作特点的基础上,提出安全稳定分析与控制决策支持智能化的主要特征：自动化和自适应性。介绍了自动化的安全稳定分析计算技术,包括输入数据准备、任务执行和输出结果的自动化处理;阐述了自适应电网运行工况、外部环境和硬件运行状态的安全稳定分析技术,包括调整应用功能的输入数据和妥善处理安全稳定性交互影响,以及根据分析计算任务要求动态优化调度计算资源。这些技术已用于安全稳定综合防御系统,提高了分析结果的适应性和分析计算的效率,在电网运行规划、计划安全校核、超短期安全态势预测、调度操作安全校核和在线分析与控制等电网调度运行管理中发挥作用。     

Hydrophilic and hydrophobic materials and their applications

Wettability of a material’s surface plays a significant role in how fluids interact with such surfaces. Wetting behavior is universal but can vary depending on the chemical nature of the solid and liquid phases. Plants and animals adapt to their environment by having evolved special properties. These properties are such as hydrophilic and hydrophobic. Hydrophilic surface has a strong affinity to water and spreading of water on such surface is preferred. The degree of hydrophilicity of the substance can be measured by measuring the contact angle between the liquid and solid phases. Hydrophobic materials are known as non-polar materials with a low affinity to water, which makes them water repelling. A contact angle of less than 90° indicates hydrophilic interaction where as an angle greater than 90° indicates a hydrophobic interaction. More recently, superwetting such as superhydrophilicity has been receiving an increased focus in the literature due to its potential significance. Superhydrophilic surface has a contact angle of less than 5°.

The fabrication of hydrophilic materials can be carried out in two main ways: depositing molecules on surfaces or modification of surface chemistry. Both methods have been successful historically in achieving their intended purposes. Hydrophobic and superhydrophobic materials can be produced with many fabrication methods such as layer-by-layer assembly, laser process, the solution-immersion method, sol-gen techniques, chemical etching, and Hummer’s method.

The applications of such an important property are significant. For example, hydrophilic surfaces can be used in anti-fogging applications, biomedical, filtration, heat pipes, and many others. Hydrophobic and superhydrophobic materials have been successfully applied in many sectors, such as: (I) the removal of petroleum from aqueous solutions, (II) applied to plastic, ceramics, and mesh to contribute to the oil removal from aqueous solutions, (III) hydrophobic layers have a strong self-cleaning effect on plastics, heat pipes, metals, textiles, glass, paints, and electronics, (IV) hydrophobic layers improve the anti-freezing behavior of heat pipes which prevents unwanted build-up and (V) they function as a water and dust protecting coat on electronics.

The presence of this property is historic but there is still a huge potential for development for its applications in many sectors such as water treatment, heat transfer applications, biomedical devices, and many more.     

Defect and impurity diagnostics and process monitoring

The review focuses on four areas of defect and impurity diagnostics: (i) the determination of parasitic resistances, (ii) quantum efficiency analysis including light-beam-induced current measurement systems which use spectrally resolved currents to determine local recombination in solar cells, (iii) methods to determine the recombination properties in solar cell precursors and (iv) techniques suitable for the recognition of the type of impurity or defect, which is responsible for increased recombination. In general, emphasis is on those methods, which are capable of delivering spatially resolved information. The use of the specific metastability features of a defect for its identification is exemplified. In addition, carrier lifetime spectroscopy methods utilising the temperature or the injection dependence of defect recombination are outlined.     

铁道机车车辆轮轨的摩擦磨损与节能降耗

阐述了铁道机车车辆轮轨摩擦磨损的现状;研究了内燃机车车轮、闸瓦和钢轨的消耗数量及相应的维修费用;指出了采用适当的新技术之后,在节能降耗方面会产生显著的经济效益。     

Hydrogen and electricity from water and light

Four self-driven photoelectrochemical hydrogen producers: n-TiO₂/p-CdTe, n-TiO₂/p-GaP, n-SrTiO₃/p-CdTe and n-SrTiO₃/p-GaP were constructed and examined in 1 M NaOH. the current-potential curves of the individual electrodes and the current-cell voltage relationships were measured. Cell current-density measurements versus time demonstrated that the output of each cell is stable for at least 12 h. the n-SrTiO₃/p-GaP cell under xenon light irradiation was the most efficient at 0·7 per cent. the n-TiO₂/p-GaP cell was estimated as the most efficient under solar light at 0·1 per cent. the stability of p-CdTe and its energy gap of 1·5 eV make it a prospect for use as a photocathode in future photoelectrochemical hydrogen producers.     

能源的开发利用与节能

在节能与环保问题成为当今全球性重要研究课题的情况下,笔者对中国能源的现状、新能源开发问题和在用车辆的环保节能问题进行了研究探讨。认为我国应加大开发可再生能源、核能源的力度,开发城市生活垃圾的新能源,找出在用柴油车实现环保节能的一些新措施。     

国内外能耗监测控制管理理论与实践

能耗监测是能源管理中的重要环节,国外不少国家在这方面都进行了积极的努力,制定了一些相关政策,并取得了一部分研究成果.我国于上世纪90年代初就出台了关于能耗监测的有关规定,2007年颁布的《单位GDP能耗监测体系实施方案》规定了能耗监测的主体、主要内容和指标.工业、交通运输和建筑是我国三大“耗能大户”,因此能耗监测研究和管理实践也主要集中在这三个领域.信息技术的发展为工业企业的能耗监测提供了基础平台,运用计算机信息技术对能耗实行现代化管理,成为企业实现信息化管理、降低成本的一种重要手段.道路交通约占我国交通运输业能耗的75％,因而对道路交通能耗的监测是交通运输业能耗监测的主要任务,而对机车能耗的监测是铁路运输能耗监测的主要内容之一.建筑能耗监测主要针对大型公共建筑,通过信息化手段进行信息采集及能耗监测.目前有关能耗监测的研究还处于起步阶段,尚未全面展开,能耗监测技术还不成熟,监测设备也不齐全.今后除了要继续探索能耗监测技术以外,还应重点加强对主要行业能耗监测控制管理体系的研究.     

The roles of science and technology in energy and environment research and development

Countries are becoming increasingly aware of the importance of science and technology in relation to national development and the necessity of formulating a concise science and technology policy. The need to strengthen and orient the scientific and technological infrastructure in line with national development goals, through more effective use of an available qualified work force and the higher education system, is becoming widely recognized. Consequently, appropriate methods of assessing the impact of science and technology on national development are needed so that efforts are concentrated on areas potentially having substantial impacts. Numerous planning studies have been undertaken to this end, particularly by international organizations such as UNESCO, UNIDO, OECD and IEA. This study examines the inter‐relationships of the disciplines of science and technology with energy and environment research and development (R&D) activities, particularly for developing countries. The connections between these topics are discussed along with some basic methods that can be used to exploit the relations. Some illustrative examples are presented. It is anticipated that the present study will serve as a preliminary step for more comprehensive work by providing an example of the utilization of formal methods in formulating science and technology policy for energy and environment R&D. Copyright © 2001 John Wiley & Sons, Ltd.     

火电厂TSI安装调试及常见故障诊断和处理

火电机组TSI探头的安装与调试是一个较为复杂和精细的工作.是火电厂热控安装不可或缺的最重要的组成部分.文章对各种测量探头的原理进行了分析,理论结合实际,将原理图和现场安装图进行对照,通俗易懂.对这些TSI探头在实际安装时应注意的细节问题做了详尽的阐述,同时对试车过程中出现的问题进行了分析并提出了处理措施.对火电机组汽轮机本体热工仪表安装工作有一定的指导意义.