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1.
In this paper, a novel algorithm is proposed for balancing water looped network in steady state through a fully automated general framework of hydraulic networks regardless of their topological complexity. The model is developed by combining the following two steps, firstly a set of independent loops are identified based on a graph theoretical analysis in a looped network. Further the second step is devoted to the equilibrium process by determining the flow rate distribution within the network ducts and the pressure in the delivery nodes. The above such equilibrium process gives rise to a system of non linear algebraic equations which are solved numerically using both Hardy Cross (HC) and Newton Raphson (NR) methods. In HC method, the flow correction term is modified and a generalized expression is given to consider various possibilities of independent loops selection. Some real networks topologies that were commonly used as benchmarks, for testing various independent loops selection algorithms, are taken as case studies to apply the general automatic framework for hydraulic network analysis. Such network analysis enhances proving the applicability as well as the effectiveness of the proposed approach. Also, during the equilibrium procedure, it is proved that NR method is capable of producing accurate results and it converges more rapidly comparing to the widely used HC method. Moreover, it is demonstrated that NR’s iterative process, contrary to HC’s one, converges to reliable results even with a choice of random initial flow rates which makes a NR algorithm quite simple to implement without affecting the accuracy of the results.  相似文献   

2.
Urbanization can significantly increase the load on aging, inefficient and already strained sewer infrastructure, resulting in catastrophic pipe failure, unwanted spillage, property damage, and serious threat to public health. Urbanization can also dramatically alter the natural water cycle, resulting in diminished water quality, increased frequency and severity of flooding, channel erosion and destruction of aquatic habitat. Recent advances in smart water network (SWN) modeling technology have played a crucial and growing role in addressing these challenges. SWN technology has equipped practicing engineers with a comprehensive set of analytical decision making tools designed to help them preserve structural integrity, manage and reduce the risks of sewer overflow and urban runoff, improve resiliency and keep their urban drainage networks operating well into the future. These advances propel routine conveyance system analysis from basic planning and design to two-dimensional surface/subsurface flow modeling, real-time operation and control, analytical risk-based asset integrity and condition assessment, and optimal selection and placement of green infrastructure based on cost and effectiveness. SWN is providing critically needed support to federal, state, and local agencies and watershed practitioners — not only in optimizing their integrated water management and adaptation strategies, but in ensuring sustainable drainage, addressing environmental quality restoration and protection needs in urban and developing areas, and improving communities’ resiliency. It is also within the grasp of utilities of all sizes, but they need to seize the opportunity.  相似文献   

3.
While the Latin American and Caribbean Region has an abundance of water resources, the uneven distribution of water and the rapid growth of urban areas have created a set of water management problems which, if left unresolved, are projected to lead to a water crisis of hemispheric proportions during the next century. Shrinking foreign aid and experience gained during the past four decades are changing the traditional mechanisms of technical cooperation between developed and developing nations. Building on the momentum of the Earth Summit (1992), which stressed the need for mechanisms for water resources information exchange, the First Inter-American Dialogue on Water Management (1993) called for the establishment of an Inter-American Water Resources Network (IWRN) to distribute and exchange information on water issues, promote technology transfer, and share water management experiences in the western hemisphere. To date, 22 governments have officially designated water agencies to represent them on the IWRN as country focal points. Current network activities consist of the preparation of directories of water and water-related organizations, educational opportunities and existing networks in the western hemisphere; publication of a newsletter; and operation of an electronic forum and several World Wide Web sites on the Internet. Future activities, defined in part by the Second Inter-AmericanDialogue on Water Management held in Buenos Aires in September 1996, will emphasize the establishment of a regional and sub-regional Internet-based water information network with linkages to the global water resources community, regional dialogues on water management, increased cooperation between all parties in transboundary river basins, and endorsement of a number of recommendations for strengthening integrated water resources management.The Third Inter-American Dialogue on Water Management will be held in Central America in 1999.  相似文献   

4.
This paper presents a methodology for the application of the Smart Water technology to detect water leakage. This methodology consists in the use of the traditional water balance method together with the minimum night flow approach. This procedure has been applied to a large-scale pilot project conducted at the Scientific Campus of the University of Lille, which is the size of a small town. The water network of the campus is monitored by a set of sensors that record and transmit, in real-time, the hydraulic parameters of the water system. Analysis of real-time data has allowed the verification of water balance and the estimation of water losses level in the network. The paper presents an improvement of the application of the minimum night flow method, which is based on the determination of flow thresholds. A leak alarm is generated if the night flow exceeds the thresholds. This data analysis methodology provides the capability to detect the pipe bursts quickly, thereby reducing the runtime of leakage. The application of the improved method allowed the detection of 25 unreported leaks and decreased the Non-Revenue Water (NRW) level by 36%.  相似文献   

5.
Mu  Tianwei  Lu  Yan  Tan  Haoqiang  Zhang  Haowen  Zheng  Chengzhi 《Water Resources Management》2021,35(8):2325-2341

A novel network partition model is presented within the water distribution system (WDS). Firstly, random walk community detection (RWCD) is employed to divide WDS into different partitions concerning the average pressure of nodes. Then, network reliability is assessed based on hydraulic reliability estimation (HRE), mechanical reliability estimation (MRE), flow entropy function (FEF), and network resilience (NR), via optimizing boundary pipes by the non-dominated sorting genetic algorithm-II (NSGA-II). Finally, pressure-reducing valves (PRVs) are set to pipes for acquiring optimized partitions. The Open Water Analytics (OWA) toolbox and Matlab-2018b is adopted as a hydraulic calculation tool for these extended period simulations (EPS). Seven cases of WDSs were used to verify the practicability of this model. The results demonstrate that network reliability is improved effectively after partitioning and optimizing.

Graphical Abstract
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6.
A proper division of a Water Distribution System (WDS) into District Metered Areas (DMAs) provides important management benefits particularly with regard to leakage detection through water balances, control and optimization of pressure so as to reduce leakage, implementation of monitoring, warning and emergency acting systems against accidental or intentional water contamination. This paper presents a new methodology that combines a suitable modularity-based algorithm for the automated creation of DMA boundaries and convincing practical criteria for the DMA design. A further plus of the proposed methodology is its ability to identify many technically feasible solutions that can be subsequently economically assessed. The successful applications of the proposed methodology to a real case study, already tested by other authors, has proven its effectiveness for the DMA design in existing water distribution systems.  相似文献   

7.
Li  Juan  Zheng  Wenjun  Lu  Changgang 《Water Resources Management》2022,36(7):2309-2325

In the water supply network, leakage of pipes will cause water loss and increase the risk of environmental pollution. For water supply systems, identifying the leak point can improve the efficiency of pipeline leak repair. Most existing leak location methods can only locate the leak point approximately at the node or pipe section of the pipe network but cannot locate the specific location of the pipe section. This paper presents a framework for accurate water supply network leakage location based on Residual Network (ResNet). This study proposes a leak localization idea with a parallel classification and regression process that enables the framework to pinpoint the exact position of leak points in the pipeline. Furthermore, a multi-supervision mechanism is designed in the regression process to speed up the model’s convergence. For a pipe network containing 40 pipes, the positioning accuracy of the pipe section is 0.94, and the MSE of the specific location of the leakage point is 0.000435. For the pipe network containing 117 pipes, the positioning accuracy of the pipe section is 0.91. The MSE of the specific location of the leakage point is 0.0009177. Experiments confirm the robustness and applicability of the framework.

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8.
智能水电厂自动化系统总体构想   总被引:1,自引:0,他引:1  
智能水电厂的总体目标应该是通过智能化改造,进一步提高水电厂生产及管理的自动化水平,提高设备的安全运行水平,提高全厂经济效益,为实现状态检修创造条件.建设智能水电厂,目的是提升水电厂的安全和经济运行水平,进一步提高机组的可观性、可控性和可调性,提升网厂之间的智能协调水平.由于国内在智能水电厂方面刚刚起步研究,加强智能水电厂的概念、目标、功能、系统配置及系统问互动的研究,有利于推动计算机监控系统、机组状态检修、水电厂经济运行等方面研究的展开.  相似文献   

9.
This paper explores the possibility of using a calibrated rainfall-runoff model as a decision-making tool in sustainable water sharing. Designing institutional arrangements for runoff sharing process in the case of a sub-catchment spread across geopolitical boundary is challenging. For the water sharing arrangement to be sustainable, it must be founded on realistic runoff predictions. The climate uncertainties make the water sharing process more complex and complicated. This context warrants a decision-making tool for helping the water sharing policy makers and its managers in taking a decision. In this study, a decision-making tool for sharing the waters of Parambikulam sub-catchment in Southern Peninsular India is developed. RRL (Rainfall-Runoff Library), RAP (River Analysis Package) and SCL (Stochastic Climate Library) of eWater toolkit are used for developing this tool. In the decision making, it also incorporates the runoff change prediction portrayed in India’s second national communication to UNFCC. The existing institutional arrangement for water sharing of this sub-catchment is revisited in the light of findings of this study. Paper is concluded by explaining how it is useful in synthesizing a range of options on designing a new water sharing paradigm for this sub-catchment.  相似文献   

10.
有限元网格的区域划分是影响有限元并行计算效率的关键因素,介绍了几类有限元并行计算的图剖分方法,并在此基础上提出了一种改进的划分方法,经过验证这种方法是有效的,在负载均衡度相同的情况下,能有效地减少并行计算的通信量。  相似文献   

11.

Water distribution systems (WDSs) today are expected to continuously provide clean water while meeting users demand, and pressure requirements. To accomplish these targets is not an easy task due to extreme weather events, operative accidents and intentional attacks; as well as the progressive deterioration of the WDS assets. Therefore, water utilities should be ready to deal with a range of disruption scenarios such as abrupt variations on the water demand e.g. caused by pipe bursts or topological changes in the water network. This paper presents a novel methodology to automatically split a WDS into self-adapting district metered areas (DMAs) of different size in response to such scenarios. Complex Networks Theory is proposed for creating novel multiscale network layouts for a WDS. This makes it possible to automatically define the dynamic partitioning of WDSs to support further DMA aggregation / disaggregation operations. A real, already partitioned, water utility network shows the usefulness of an adaptive partitioning when the network is affected by an abnormal increase of the peak demand of up to 15%. The dynamic DMA reuses the assets of the static partitioning and, in this case, up to the 82% of resilience is restored using 94% of the assets already installed. The results also show that the overall computational and economic management costs are reduced compared to the static DMA partition while the hydraulic performance of the WDS is simultaneously preserved.

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12.
The method of material flux analysis is applied as an instrument for the early recognition of environmental problems in an urban region of developing countries. It is shown that, even with poor data quality and quantity, it is possible to apply the method in Tunja, an urban region in Colombia. With sensitivity analysis monitoring points are developed to attain 'early recognition' concerning changes in water quality and quantity in this region. Using the scenario technique it is shown that, owing to the low dilution capacity for sewage in the region, surface water cannot reach the quality of water at a natural state even if technical measures used in industrialized countries are taken.  相似文献   

13.
林坚 《红水河》2013,32(1):63-68
配电网作为整个电力系统生产和供应的最后环节,其安全经济的运行直接影响国民生产与生活。配电网通信是配电网实现综合自动化必不可少的组成部分,是配电网自动化的基础。如何建设适合配电网自动化通信系统是文章讨论的主题。文章对目前配电网几种通信方式进行分析,为智能配电网通信方式的选择提供参考。  相似文献   

14.
15.
针对传统分区方法电气距离定义的缺点,提出一种新的电气距离即空间电气距离。依据系统中各节点之间无功电压变化关系,将系统各节点映射到一个多维空间中,节点之间的空间距离便是其电气距离,依据此距离将各节点进行归类,从而把无功电压控制分区问题转化为数学上的空间聚类问题。针对无功电压控制分区的特点并借鉴聚类算法,提出免疫 — 中心点聚类的无功电压控制分区算法并将其运用于IEEE 118节点系统,对分区结果进行分析并与其他算法结果比较,验证所提出的算法的准确性和可行性。  相似文献   

16.
连续两年的极端暴雨天气使山东省寿光市遭遇了严重水患,暴露了水利信息化建设中的短板。为此,本文结合山东省寿光市水利信息化现状和实际需求,从建设目标及建设原则入手,详细介绍了寿光市依托大数据、物联网、地理信息系统等新一代信息技术搭建的智慧化平台总体框架及功能,实现了域内水利工程的动态监管、河道防汛的实时管护及对公众的信息服务,为智慧水利在县域的实现提供了技术支撑。  相似文献   

17.
Land and water degradation due to on-site soil/nutrient loss and off-site pollution/sedimentation are serious environmental problems. Landscape planning and management tools are essential to implement best management practices targeted at locations where they are needed most. Although many soil/water-landscape studies have been published in the last 2 decades, progress in developing operational tools for supporting landscape planning to minimize land and water degradation in developing regions is still modest. Some of the existing tools are data demanding and/or complicated to be useful to data scarce regions. Some require detailed understanding of the hydrological and modelling processes and thus less applicable to local stakeholders involved in land use planning and management. A user-friendly LAndscape Planning and MAnagement Tool (LAPMAT) developed to facilitate land management decision-making. LAPMAT is a menu-oriented interactive graphical user interface that can aid decision makers identify hotspot areas of soil erosion and evaluate the effects of alternative land use management practices at a catchment scale. The modelling framework and its interfaces are designed to guide the user through a series of menus that: 1) allow input model parameters, adjusting coefficients, visualizing input parameters and executing the model; 2) enable changing land use and management practices and re-evaluating potential consequences; 3) allow viewing results in tabular, graphical or map form side-by-side; and 4) (re)-evaluating the respective impacts of management/conservation options. The framework has been applied to assess the severity of soil erosion and simulate the impact of different land management practices using the Revised Universal Soil Loss Equation (RUSLE) adjusted for sediment delivery ratio in an example catchment of northern Ethiopia. The results showed average sediment yield rate of 55 t ha?1 y?1. Conservation measures targeted at high soil loss areas and gullies gave the maximum reduction in sediment yield by about 80 %. Since LAPMAT allows users handle the selection of management/planning options and provide fast and responsive outputs, it can assist in effective multi-stakeholder negotiations over land-use planning where the minimization of land/water degradation is the ultimate goal.  相似文献   

18.
对一种适用于智能变电站的微机保护装置集中式网络打印方案进行了研究。通过分析微机保护装置的组屏安装就地化打印方式存在诸多不足和微机保护装置的信息打印业务,根据智能变电站的网络化技术特征,提出了一种新的集中式网络打印方案,并将该方案成功应用于新一代智能化变电站自动化系统中。该方案以打印服务器为中心,采用IEC61850通信规约,可实现打印格式的灵活控制,打印输出效果更加美观,同时还具备与电力管理信息系统的文档接口功能,因此是智能变电站技术创新发展的重要方向之一。  相似文献   

19.
Water utilities particularly in the developing countries continue to operate with considerable inefficiencies in terms of water and revenue losses. With increasing water demand and scarcity, utilities require effective strategies for optimum use of available water resources. Diverse water loss reduction options exist. Deciding on which option to choose amidst conflicting multiple criteria and different interests of stakeholders is a challenging task. In this paper, an integrated multi-criteria decision-aiding framework for strategic planning of water loss management is presented. The PROMETHEE II method was applied within the framework in prioritizing water loss reduction options for Kampala city. A strategic plan that combines selective mains and service lines replacement and pressure management as priorities is the best compromise based on preferences of the decision makers and seven evaluation criteria characterized by financial-economic, environmental, public health, technical and social impacts. The results show that the most preferred options are those that enhance water supply reliability, public health and water conservation measures. This study demonstrates how decision theory coupled with operational research techniques could be applied in practice to solve complex water management and planning problems.  相似文献   

20.
Water shortage is experienced in different parts of the world in different magnitude. In certain countries, water deficit is a regular phenomenon and in some other countries it happens for a short duration, due to failure of any component in the system. Shortage of water at source can be best tackled by distributing the available water equally among the consumers. This paper deals with the design of water distribution network capable of equitable supply during shortage in addition to the satisfactory performance under non-deficit condition. Performance of a typical water distribution network, with shortage of water at source is illustrated in detail. Head dependent outflow analysis with extended period simulation, is used to determine the actual supply from each node to consumers. Relationship between duration of supply and volume available at source as well as supply from each node are established for understanding the behaviour of network under low supply situation. A term “inequity” which is the maximum difference in supply demand ratio among different consumers is presented. This is based on the actual performance of the network instead of surrogate measures, generally used for reliability. It is illustrated that the maximum “inequity” in supply in a network during the entire duration of supply can be estimated with single analysis. Design of a water distribution network, duly considering equity in addition to the cost minimization and minimum head requirement is presented. Genetic Algorithm is used for solving this multi objective problem. The solution technique is illustrated using two benchmark problems, namely two loop network and Hanoi network. Results show that considerable improvement in equitable supply can be achieved with additional investment on pipes above the least cost solution. Hence it is better to design networks duly considering deficit condition for better reliability. It is also illustrated that it will be difficult to improve equity beyond a limit for a given network, through selection of different pipe diameters.  相似文献   

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