水电机组运行设备状态检修的实施及关键技术(Ⅱ)

基于国家电力公司颁布的《水电厂开展设备状态检修工作的指导意见》 ,介绍了当前中国水电厂开展状态检修工作的发展状况及存在的问题 ,并结合水电厂运行实践 ,重点叙述了水电机组运行设备状态检修实施的主要环节及关键技术     

水电机组运行设备状态检修的实施及关键技术(Ⅰ)

基于国家电力公司颁布的《水电厂开展设备状态检修工作的指导意见》,介绍了当前中国水电厂开展状态检修工作的发展状况及存在的问题,并结合水电厂运行实践,重点叙述了水电机组运行设备状态检修实施的主要环节及关键技术。     

精益检修策略应用实践

介绍在三峡电厂、葛洲坝电厂先进设备状态监测技术及多年设备检修经验的基础上,成功发展了结合状态检修、定期检修和事后检修等多种检修模式的精益检修策略,并就精益检修策略的实施条件、方法及实施成果作了详细的阐述。     

龙滩水电站多组态数据分析平台的研究与开发

水电厂由传统的“计划维修”方式到更具科学性的“状态检修”方式转变,是国内乃至国际水电行业的发展趋势。而要实现“状态检修”,必须预知设备健康状况。设备健康状态分析必须来源于大量的运行、维护数据。为此,龙滩电厂正在着手研究开发充分利用计算机监控系统等监测运行数据,能够灵活配置的多组态数据分析平台,以实现运行数据的科学、高效利用,为设备状态检修奠定基础。     

流域水电站设备远程状态分析及辅助诊断系统建设探讨

澜沧江公司是除三峡以外国内第二大流域发电公司,截止2018年7月,投产水电装机规模突破2 000万kW,其中10万kW及以上机组51台。公司检修管理模式以"计划检修"为主,随着监测、诊断分析技术的不断进步,在推进状态检修的新要求下,结合流域电厂计算机监控系统、在线监测系统的配置情况,依据《水电站设备状态检修管理导则》有关要求,对流域水电站设备远程状态分析及辅助诊断系统建设的构架、功能、建设思路进行了研究和探讨。     

广西原恶滩水电厂探索“状态检修”成效

状态检修作为设备检修管理理念已经被国内水电同行接受，本文介绍了广西原恶滩水电厂探索状态检修的情况，对水电机组状态检修进行了有益的尝试，谨供同行参考。     

水电机组状态检修的实施及关键技术

遵照国家电力公司颁布的《水电厂开展设备状态检修工作的指导意见》的文件精神，介绍了当前我国水电厂开展状态检修工作的发展状况及存在的问题，并结合水电厂运行实践，重点叙述了水电机组状态检修实施的主要环节及关键技术。实施状态检修的主要环节是建立“四库”。实施状态检修的关键技术包括：实施集成系统；监测点的选择及布置；一次传感元件的选型及标定；信号分析及处理；机组故障类型的确定；专家系统的建立等。     

浅谈水电设备状态检修

分析了水电设备实行状态检修的必要性和可能性,提出了水电设备实行状态检修应注意的几个问题,介绍了国内外状态检修工作概况及华中电网水电设备状态检修工作现状。     

水电机组状态监测

水电机组计算机监控系统正在越来越多的电厂实施，机组检修模式也在从计划检修向状态检修过渡，因此必需实施水电机组状态监测，因为它是上述两项工作的基础。水电机组状态监测涉及多种变量，多种方法，是需要深入探讨和研究的。本文介绍了世界上先进的监测技术，提出了参量的监测方式，推荐了成熟的监测仪表和元件，目的在于为正开展这项工作的电厂提供参考，抛砖引玉。     

大渡河流域水电机组故障诊断与检修策略研究

鉴于水电行业目前的技术还不足以实行水轮发电机组所有设备的状态监测要求,因此也不适合推广应用于大渡河流域各电站机组的检修.经过研究与实践,行业认可的检修是一种综合或复合的检修方式.     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

基于BP神经网络-马尔科夫链模型的隧道围岩位移预测

在隧道工程施工中,围岩位移预测起着很重要的作用。将BP神经网络-马尔科夫链模型引入到隧道围岩位移预测中来,通过对训练样本的学习,利用BP神经网络实现了对位移时间序列的滚动预测,同时得到了实测值与预测值的相对误差;在此基础上利用马尔科夫链对相对误差进行修正,有效地提高了预测结果的精度。并将该模型应用于某公路隧道拱顶下沉位移时序预测中,结果表明该模型具有精度高、科学可靠的特点,为隧道围岩变形的预测提供了新的途径。     

Short communication. Pipelines as a refuge for freshwater snails

In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment.     

浙江省水域调查录入系统的设计和应用

浙江省水域调查录入系统将调查数据与电子地图相整合,对分类水域数据进行统计计算,并对输入数据进行合理性和完整性检查,得到调查范围内现有水域的详细数据,实现了水域调查数据输入、计算、统计和查询的数字化管理,提高了工作效率和工作质量,为各地下阶段水域保护规划编制和水域管理工作提供了数据支持。对该系统的设计原则、功能和技术设计等作了介绍。     

基于CT-连续加荷水泥乳化沥青混凝土细观损伤规律研究

利用CT技术对水泥乳化沥青混凝土的细观损伤过程进行实时扫描观测,获得了混凝土试件在连续加荷下的CT图像。通过采用直观分析法、CT数分析法、CT数与损伤变量关系3种方法分析表明,水泥乳化沥青混凝土的破坏过程可分为压密、扩容、裂纹扩展、破坏4个阶段,同时混凝土在受压过程中具有韧性,在极限荷载之前各断面处于压密和微扩容的强化阶段,极限荷载之后混凝土从损伤到破坏发展比较平稳。     

Automated system for removal and pneumatic transport of fly ash from electric precipitator hoppers

A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system, configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants of dry ash utilization and the advantages of producing of size-separated particles are considered. __________ Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008).     

The flood pulse advantage and the restoration of river-floodplain systems

The ‘flood pulse advantage’ is the amount by which fish yield per unit mean water area is increased by a natural, predictable flood pulse. Evidence for this increase is presented from tropical and temperate fisheries. It is argued that increasing multispecies fish yield by restoring the natural hydrological regime is consistent with increasing production of other trophic levels and with restoration from ecological and aesthetic viewpoints. When applied to a river-floodplain system, this restoration would provide a large, self-sustaining potential for recreation, commercial exploitation, and flood control. An interim ‘natural flood pulse’ restoration approach is proposed for systems modified for navigation. This approach approximates the natural hydrological regime in a river reach and is intended as a first step in the long process of restoring the watershed.     

浅谈天湖水电站水轮机运行故障及处理措施

简述天湖水电站投运以来各种故障的表现形式，分析其原因，提出了相应的处理方法及措施，并对合理利用国内外设备提出建议。