潘家口抽水蓄能电站2号机组导叶漏水量测试研究

本文介绍了在工作闸门密封条部分脱落的情况下,如何对潘家口抽水蓄能电站2号机组导叶漏水量进行测试,分别得出了工作闸门漏水量和导叶漏水量,与GB/T 15468-2006《水轮机基本技术条件》中的技术条款对比显示,2号机组的导叶漏水量满足要求,为机组的安全稳定运行提供了技术支撑.     

水轮机筒阀安装质量控制及关键指标优化

<正>1水轮机筒阀应用及功能概述目前,水轮机筒阀已先后在国内漫湾、小浪底、大朝山、小湾、锦屏、溪洛渡等大中型水电站广泛使用。筒阀具有运行可靠、结构简单、操作灵活的特点,在控制厂房尺寸、减小水力损失,保护导水机构、提高经济性等方面具有突出优点。在机组停机时,筒形阀处于关闭状态,筒体落下处于座环固定导叶与活动导叶之间,上端紧压布置在顶盖上的密封条,下端紧压布置在底环上的密封条,从     

水轮机活动导叶立面软密封形式的应用

水轮机活动导叶立面软密封形式广泛应用于中、低水头机组,过去多采用圆形橡皮条的结构,此结构密封条制造及安装工艺简单,但容易脱落,导致立面密封失效。根据国内水电站运行和检修经验,对导叶立面密封失效原因进行了分析,阐述了各类型软密封的结构和特点,为水电站活动导叶立面软密封应用及改造提供依据。     

混流式水轮机导叶漏水分析及处理

水轮机导叶漏水不仅造成水资源的浪费,同时对机组的安全稳定运行均造成影响。宝珠寺在机组解体大修过程中,检修人员对活动导叶进行了补焊、打磨处理以及线型修复,将变形底环返厂加工,并在底环抗磨板部位新增密封条,对导叶套筒密封以及压垫环进行了处理和更换。机组检修后,用容积法对该机组导叶漏水量进行了测量,导叶漏水量由0.75 m3/s降低到0.408 m3/s,按照机组年均停机时间计算,全年可增发电量140万千瓦时,基本达到了项目预期。     

影响导叶立面间隙调整因素分析

阳蓄电站机组为400MW的混流式水泵水轮机机组，导叶立面间隙使用传统的捆绑法进行调整，在1号机组调整的过程中，出现导叶回弹现象和导叶立面间隙始终无法收敛，使导叶立面间隙调整工期达7d之久，远远超出计划工期。针对导叶回弹现象和导叶立面间隙无法收敛进行了分析，并对处理措施进行详细阐述，且在2、3号机安装过程中避开了影响导叶立面间隙调整的因素，确保2、3号机导叶立面间隙调整在计划工期内完成。     

高水头混流式水轮机导叶密封结构改进与发展

导叶密封问题是制约高水头混流式水轮机大修周期的关键性问题，它在国内一些高水头电站反映相当突出。导叶密封的本质是为了减小导叶漏水量。本文提出了根据水轮机导叶端、立面设计间隙来计算导叶漏水量一般公式，并据此分析影响导叶漏水量的主要因素，从而提出导叶蜜封结构改进的意见。     

导叶双列叶栅位置对水力性能的影响

基于N—S方程和标准κ-ε紊流模型，用数值模拟的方法分析了固定导叶和活动导叶的相对位置关系对水力性能的影响；主要分析了固定导叶出流角与活动导叶进水角的匹配关系，活动导叶的三种不同位置的速度矢量和压力分布，活动导叶的几何出水角与水流角的关系，在分析了三种不同位置时的水力损失后，给出了固定导叶与活动导叶的最佳位置关系，提出了双列叶栅设计时的最优设计参数。     

导叶摩擦装置在西霞院反调节水电站的应用

导叶摩擦装置作为一种新型的导叶保护装置，在导叶与拐臂之间采用摩擦片传递力矩，取代了导叶拐臂之间传统的剪断销；其结构紧凑、适用性强、运行可靠、维护方便等优越的特性，使得它在水电厂有着广泛的应用前景。     

基于UG的水轮发电机组活动导叶内部流场模型的构建

对混流式水轮发电机组中的重要过流部件．活动导叶进行内部流场建模。结合导叶相关参数绘制出了导叶翼型，通过调整导水部件的特征参数建立了在允许最大开度α0max下，进口角αj=45&#176;的活动导叶内部流场平面模型。最后，基于UG的自由曲面造型功能，构建了活动导叶的内部流场三维实体模型，为后续内部流场动力特性分析奠定了良好的基础。     

导叶角度对轴流泵高效区运行范围的影响

为了研究导叶角度对轴流泵高效区运行范围的影响，采用CFD和模型试验对不同导叶角度下轴流泵水力性能进行数值模拟计算，并且进行内流场比较分析。结果表明，通过改变导叶角度后，优化导叶在设计和大流量工况下的内部流场更加均匀合理，导叶优化后的轴流泵最高效率为87.53%，与初始导叶方案相比，配优化导叶的轴流泵高效区运行范围扩宽了近1.36倍。最后通过模型试验对比分析，验证了数值计算的可靠性。研究结果可为提高轴流泵高效区的运行范围提供参考。     

Grassed buffer strips as nitrate diffuse pollution remediation tools: management impact on the denitrification enzyme activity.

The management of grassed buffer strips proved to be an efficient remediation technique in controlling nitrogen losses to surface water. In south Belgium, agri-environmental policies have encouraged farmers to seed buffer strips along rivers, in zones where the soil was previously devoted to agricultural production. We wanted to assess how important denitrification is in a buffer strip in comparison with a cropped field. The study investigated the denitrifiying enzyme activity (DEA) of two contiguous buffer strips with different management stories. The eastern part of the buffer strip was seeded in 1999. The western part of the buffer strip is a piece of crop field abandoned by the farmer 20 years ago and not managed for the last 10 years. This experimental study demonstrates that the denitrification enzyme activity in a riparian buffer strip is significantly higher than in the adjacent cropped field (3.67 and 2.12 mgNkg(-1)d(-1) respectively). The DEA was significantly different between the two buffer strips under comparison, assessing that the management of the buffer strips has a dominant effect on DEA. The old unmown buffer strip is potentially more efficient in the nitrate removal process than the 6-year-old seeded buffer strip.     

Emission reduction by multipurpose buffer strips on arable fields.

In the area managed by Hollandse Delta, agriculture is under great pressure and the social awareness of the agricultural sector is increasing steadily. In recent years, a stand-still has been observed in water quality, in terms of agrochemicals, and concentrations even exceed the standard. To improve the waterquality a multi-purpose Field Margin Regulation was drafted for the Hoeksche Waard island in 2005. The regulation prescribes a crop-free strip, 3.5 m wide, alongside wet drainage ditches. The strip must be sown with mixtures of grasses, flowers or herbs. No crop protection chemicals or fertilizer may be used on the strips. A total length of approximately 200 km of buffer strip has now been laid. Besides reducing emissions, the buffer strips also stimulate natural pest control methods and encourage local tourism. Finally, the strips should lead to an improvement in the farmers' image. The regulation has proved to be successful. The buffer strips boosted both local tourism and the image of the agricultural sector. Above all, the strips provided a natural shield for emission to surface water, which will lead to an improvement of the water quality and raise the farmers' awareness of water quality and the environment.     

纤维增强聚合物条带约束混凝土圆柱的耐久性

通过碳化、盐溶液干湿循环下碳纤维增强聚合物布(CFRP)和玻璃纤维布(GFRP)条带约束混凝土圆柱耐久性试验,对比分析了环境作用、纤维布类型、粘着剂类型(胶Ⅰ和胶Ⅱ)对混凝土圆柱轴压性能的影响.结果表明,无论是否受环境作用,纤维增强聚合物约束圆柱的轴向应力-应变关系基本呈双线性,其强度与延性都比无约束混凝土圆柱有一定提高.碳化环境对CFRP和GFRP约束圆柱基本没有影响,盐溶液干湿循环作用后FRP条带约束混凝土柱的强度、刚度和延性降低.CFRP约束柱比CFRP约束柱耐干湿循环性能好.此外,胶的种类对耐久性也有一定影响.     

大尺寸轮胎条-黄土混合物剪切特性试验研究

为了探究轮胎条-黄土混合物(scrap tire strip-loess mixture,STR-LM)在直剪过程中的剪切特性,优化轮胎条掺量和形状特征,提高资源的循环利用率,利用Shear Trac-Ⅲ型大型直剪仪进行室内剪切试验,考虑轮胎条掺量(0%,10%,20%,30%,100%)及长宽比(u=1,2,4,8)对黄土抗剪强度的影响。结果表明:除素土及轮胎条掺量为10%之外,所有试样均表现出应变硬化特征;轮胎条掺量、长宽比的增加对提高黏聚力有显著影响,而对内摩擦角的影响较小;在试验范围内得出20%为最优掺量,STR-LM黏聚力相对于素土增加了56.5%;正应力为24 kPa和48 kPa时,长宽比为4时STR-LM取得较大的剪切强度,正应力为96 kPa和144 kPa时,长宽比为2时抗剪强度较大。STR-LM抗剪强度较素土最多提高了22%,从试验上证实了废弃轮胎改良黄土效果显著。研究成果对于将轮胎橡胶应用于湿陷黄土的地基处理及回填领域具有一定的工程指导意义。     

螺丝湾水电站水轮发电机设计

螺丝湾电站水轮发电机设计应用双鸽尾磁极联结结构，为高应力转子设计提供了新路。为解决发电机进相运行时漏磁发热和定子线棒环流问题，对传统的磁极压板结构作了改进     

溢洪道弯段糙条消能工消能率试验研究

为研究溢洪道弯段布置糙条消能工的消能特性,在新疆“635”溢洪道整治工程的研究基础上,通过量纲分析,建立了糙条消能率多因素影响模型;采用正交试验原理,对溢洪道弯段糙条消能工的布置进行正交试验并根据试验结果进行多重回归分析,得到了反映糙条布置参数和溢洪道工程参数的消能率计算公式;然后为探究各因素影响大小进行了相关性分析,并定义无量纲因子k来反映糙条消能工的综合特性。结果表明:溢洪道工程参数对消能率的影响较大,而糙条布置参数除布置角度外影响均较小;无量纲因子k与消能率和水面横比降均呈负相关关系,且改变糙条布置参数对水面横比降的影响较消能率大;k值的波动范围在0.016~0.049之间,当消能率最大时,k=0.025,水面横比降最小时,k=0.037。提出的消能率多因素影响模型是一种半理论半经验计算公式,可为实际工程设计提供理论依据。     

大型渡槽有限条法地震反应分析

根据有限条法原理,把渡槽槽身划分为若干有限条,推导出渡槽槽身结构的单元刚度矩阵、质量矩阵的显示表达式;采用空间梁单元模拟渡槽支架;联接槽身和支架的盆式橡胶支座采用弹性元件单元模拟.编写程序具体计算了某大型渡槽的自振频率,并用ansys对大型渡槽进行模态分析,对比计算结果验证本文模型的正确性.并计算了大型渡槽结构在3种工况分别输入EL-Centro、Taft、天津地震波3种地震波作用下的地震时程响应.     

动水作用下大型渡槽结构有限条法地震反应分析

根据有限条法原理,把渡槽槽身划分为若干有限条,推导出渡槽槽身结构的单元刚度矩阵、质量矩阵的显示表达式.采用空间梁单元模拟渡槽支架,联接槽身和支架的支座采用弹性元件单元模拟;采用附加质量法考虑水体的动水作用;计算了大型渡槽结构在三种工况分别输入三种地震波作用下的时程响应.     

Planning for Implementation of Riparian Buffers in the Feitsui Reservoir Watershed

The Feitsui reservoir is a major water supply source for more than five million people in Northern Taiwan. The reservoir water quality has been good, but is threatened by eutrophication due to excessive nutrient input and siltation due to sediment loads. Recently, the water authorities in Taiwan have made considerable efforts to devise strategies using watershed conservation practices for the protection of Feitsui reservoir water quality. The control of non-point source pollution (NPS) represents one of the major strategies and the use of best management practices (BMPs) is under careful consideration. The objective of this study was to assess the effectiveness and cost of a full Feitsui watershed implementation of riparian buffer strips and other appropriate conservation practices. Based on the use of watershed simulation models and a statistical relationship between pollution reduction rate and the width and slope of a buffer strip, a methodology for the planning and design of riparian buffer strips was addressed. Data from field experiments were used to calibrate the coefficients of the regression equations. Several planning scenarios were evaluated by means of cost-benefit analysis coupled with net present value method. Data on local construction and maintenance costs for the selected design and location of buffer strips were used in the analysis. Based on several cost-benefit analyses, the scenario for installing buffer strips with 30 m width and 5% slope along both sides of tributary streams in the sub-watersheds with high nutrient (phosphorus) loadings was found to be most cost effective.     

一种GIS缓冲区快速生成算法

针对目前已有的GIS缓冲区生成算法的优缺点,提出了一种基于条带分割的缓冲区生成算法,将基元缓冲区的合并计算分解到条带中,以条带中面片单元合并代替缓冲区基元合并,避免了常见缓冲区生成方法中的弧段打断、重组等复杂的计算过程,提高了算法效率。论述了采用条带分割算法构建缓冲区的实现步骤及主要技术细节,经过理论分析和实际测试表明,该算法是一个较适用的缓冲区生成算法。