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试验研究结果表明:协联曲线的不优是引起水轮发电机组振动的原因之一。通过对其进行修正,能够改善轴流转桨式水轮发电机组的运行工况,提高机组运行的稳定性和水轮机的效率。黄丹水电站轴流转桨式水轮发电机组异常振动采取的处理措施,可为研究和改善该类型水轮机组运行稳定性提供方法和依据。 相似文献
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某轴流转桨式机组水电站通过提高下游水位来增加其所在河流的通航能力。为适应新的尾水位高度,该电站对其轴流转桨式水轮机进行了改造。本文研究了改造前后该轴流转桨式水电机组调节系统的稳定性问题,通过建立单机单管轴流转桨式水电机组调节系统的数学模型,基于根轨迹分析法研究了改造前后系统参数变化时的响应特征,得出系统的变化规律和特征,以确定系统的稳定运行参数范围。此外,本文还考虑了系统随动参数变化对机组稳定性的影响。该研究为该轴流转桨式水电机组调速系统的正常运行提供了理论指导。 相似文献
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本文提出了轴流转桨式水轮机装置甩负荷过渡过程的一种合理控制理论与方式,经装有轴流转桨式水轮机的水电站现场试验证实,采用这一控制方式可以显著改善轴流转桨式水轮机装置甩负荷过渡过程的动态品质;大幅度降低水轮机蜗壳水压上升值与机组转数上升值;从而给水电建设带来重大的经济效益。 相似文献
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大渡河安谷水电站水轮发电机组为大型轴流转桨式机组,合理选择水轮机参数,对机组和电站的安全运行至关重要。对水轮机的参数选择进行了综合论证,提出了较为合理的水轮机设计参数。 相似文献
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能量效率监测是水电机组监测的重要手段之一。为了能够直观、全面地表达监测结果,从水轮机运转特性曲线图上的等效率特性曲线出发,利用相应的插值算法得到效率特性曲面,并根据效率特性曲面设计在线监测系统软件,根据所需监测的工况参数开发了一块可以连续采样的PCI采集卡,以实现水电机组的效率在线监测和直观显示。该系统已在水电厂实际运行。 相似文献
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对高效灌溉工程的五个特点和五个管理难点进行了认真分析,揭示了部分工程运转效益不佳的主要原因,并据此提出了五点改进建议:加强领导,完善主体,积极调产,有效管理,经济支持。 相似文献
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Stormwater Capture Efficiency of Bioretention Systems 总被引:1,自引:1,他引:0
Bioretention systems are increasingly being used to control the adverse effects of urbanization on stormwater quantity and quality. The stormwater capture efficiency of a bioretention system, defined as the fraction of stormwater volume captured by the system, can be used as an important index of its stormwater management performance. In this paper, an analytical probabilistic expression (APE) is derived for estimating the long-term average stormwater capture efficiency of bioretention systems. The derivation is based on the probability distribution functions of the input rainfall event characteristics and the rainfall-runoff-overflow transformations occurring on a bioretention system and its contributing catchment. In the derivation, instead of simply adopting the Howard’s conservative assumption as used in many previous studies, an approximate expected value of the surface depression water contents of a bioretention system at the end of a random rainfall event [denoted as E(S dw )] is derived and used. The accuracy of the resulting APE is verified by comparing its results with those determined from continuous simulations. The use of E(S dw ) is proven to be advantageous than the use of the Howard’s conservative assumption, it demonstrates that similar methods may be developed to analytically evaluate the stormwater management performance of other types of storage facilities for which the Howard’s conservative assumption was employed previously. 相似文献
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青藏铁路、西气东输、西电东送和南水北调工程是我国21世纪的4大工程。目前正在建设实施的南水北调工程是我国一项极具挑战性的基础设施工程,同时,南水北调东线工程也是我国水泵应用与发展的摇篮。现主要介绍了水泵效率、提高水泵的主要措施以及提高水泵效率的重要意义。 相似文献
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为了得到新投产水轮机组准确的运行特性曲线,需对原型水轮机组进行现场效率试验,简要介绍了水力机组现场效率试验主要设备、基本要求及功能。 相似文献
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通过对TBM的原理和效能预测的介绍,为隧洞工程人员提供有关TBM工作原理、技术说明、试验指标、经验公式和数据,以便对TBM的效能做出合理的估计,并为做好现场勘探工作、施工设备和方法的选择,以及为TBM的应用和管理提供帮助。 相似文献
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水机效率试验与经济效益 总被引:2,自引:0,他引:2
根据我国水电厂管理的现状,论述了水轮机效率没有被充分利用,忽视经济效益的观点。一方面是检修管理没有与水轮机效率产生的效益相结合;另一方面众多的老机组效率低下,这些老机组可以在投入不多的条件下取得提高效率(约5%)的效益。本文介绍了五种适合于现场应用的水机效率试验方法;推荐了一组针对检修管理的数学模型。 相似文献
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电力以安全为基础,现代企业视人才为生命。自石板玫投产以来,企业内部狠抓生产管理,全力保障设备安全经济运行,同时,又狠抓安全教育、技能培训,促进精神文明建设上一新台阶,努力造就了一支高素质的职工队伍,为企业的生存与发展奠定了坚实的基础。 相似文献
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Angelo Antonio Agostinho Luiz Carlos Gomes Domingo Rodriguez Fernandez Harumi Irene Suzuki 《河流研究与利用》2002,18(3):299-306
The reproductive strategies of potamodromous fish of the Plata basin involve upstream migration and passive downstream movements of eggs and larvae for dozens of kilometres. At the end of the downstream movements, the fry need marginal lagoons or bays in order for their development to be successful. The construction of reservoirs, often in series, has interrupted the movements, and is perhaps the main factor in the decrease in the abundance of migratory fish in the basin. In an attempt to lessen the impact on the upstream migrations, fish passages (floodgates, elevators and mainly ladders) have been constructed and, despite limitations, they have functioned with relative success. Some studies show the continuity of the migration of individuals captured downstream and released into the reservoir. However, downstream migration of adult migratory species is made difficult by the fact that they are, in this phase, generally reophylic (live in running water) and occupy only the upper stretches of reservoirs (fluvial and transitional zones). It would be feasible only in short reservoirs and with a very short residence time. The fact that reservoirs present calm waters, more transparency and contain a large number of small fish could delay the passive drift of eggs and larvae, exposing them to intense predation and/or promoting their settling toward deeper water, where the conditions of oxygenation are generally critical. In the remote event that the larvae reach the dam, most of them cannot be attracted to ladders (elevators are conceived only for upstream movements) or driven away from the reservoir vicinities, in as much as they have passive movements and would therefore suffer great mortality if they passed through turbines or a spillway. In reservoirs with large free stretches upstream and endowed with ample natural floodplain areas, transposition can be an useful instrument in the maintenance of genetic heterogeneity since the number of transposed specimens does not compromise the stocks of the lower stretch. These limitations, connected to the strategy of neotropical fishes, make fish passages in most situations an inadequate instrument for preservational management. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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垂直点阵集沙仪的集沙效率 总被引:11,自引:0,他引:11
垂直点阵集沙仪是挟沙气流中输沙量垂线分布测量的主要仪器,各类垂直点阵集沙仪的集沙效率有所不同,因而相应获取的实测资料之精度也差异较大,作者将大量实测输沙量垂线分布数据与获取这些数据的集沙仪类型相联系,分析了各类垂直点阵集沙仪的集沙效率。发现在近床面区各种集沙仪的集沙效率都较低提出了“集沙效率指标”。即用近床面区实测输沙量分布与上段输沙量确定的分布在近床面区外延计算值之间的偏离程度来反映各种集沙仪的集沙效率变化特征,在风速和沙粒粒径相似的条件下,集沙效率指标值越大,对应的集沙效率也越高,单管集沙仪的集沙效率最高,一般点阵式集沙仪的集沙效率次之,台阶式点阵集沙仪的集效率最低。集沙效率指标随集沙仪类型的变化主要受集沙仪中单个进沙口高度影响,反映了集沙仪内部排气状况的重要性。通过对气流速度和沙粒粒径等因素对集沙效率影响的讨论,提出了可以通过改善近床面区集沙条件,减小集沙进沙口高度等方法来提高集沙效率的建议,这些对进一步研制高效的集沙仅都具有参考价值。 相似文献