关于渠灌区管道输水灌溉的几点思考

本文阐述了管道输水灌溉在渠灌区中的应用形式。提出在渠灌区部分有利地区发展管道输水灌溉是当前灌溉区节水改造的一个重要措施。对如何降低管网工程造价从管道输水形式、管网规划布置形式、管材选取做了一些有益的探索。作者指出将管灌区作为一个独立单元，重新确定设计灌水率是降低管网工程造价的一个重要内容。     

灌区渠系建筑物老化程度评价方法探讨

对灌区渠系建筑物老化程度评价,要求简单易行。以灌区渠系建筑物安全鉴定成果转化项目为依托,通过对现有评价方法的比对和总结,以及项目区工程概况、技术力量等方面的分析,得出采用专家评价和检测分析相结合的方式,适用于大规模的建筑物老化程度评价,并给出具体评价步骤,以供参考。     

Sensitivity Indicator for Pressurized Irrigation Distribution Systems

Water Resources Management - Providing adequate pressure at the hydrant is an issue of great importance in the operation of pressurized irrigation distribution systems (PIDS). The hydraulic...     

Development of Medium-size Canal Irrigation in West Central India

ABSTRACT

The City of San Diego, California, U.S.A. with a regional metropolitan area population of 2.5 million, which is expected to double by the turn of the centuiy, looks to recycling raw sewage as an exploratory model to help meet future water needs as traditional water resources diminish.

The City is studying aquaculture sewage treatment, augmented by ultra filtration, reverse osmosis, and carbon adsorption treatment. A pilot plant with a capacity for 25,000 GPD (94,000 l/d)? to 50,000 GPD (188,000 l/d) is operational and a 1.0 MGD (3.8 Ml/d) prototype is under construction, making this the largest system of its kind in the world.

By-products of the aquaculture program, also under investigation, include fuel, animal fodder, agricultural soil “composi”, and commercial fishery potential.

The initial results are highly promising, indicating that the process may be cost effective, energy self-sufficient, except for the reverse osmosis process, and offers an innovative technological breakthrough augmenting conventional sewage treatment, traditional water supplies, and common sources of food, feed and energy.     

浅谈农田渠道设计中输水损失量计算方法

针对经验公式在计算渠道输水损失量存在的问题和不足,考虑渠道流量损失过程是渠道水在流动过程中的动态过程,本文利用积分的方法,推导出新的计算方法和公式,并在实例中作出对比。结果显示：在短距离渠道设计时二者计算结果相差不大,都可以为工程采用,但新推求公式更精确,更适合长距离渠道设计时采用。     

Energy and Hydraulic Performance-Based Management of Large-Scale Pressurized Irrigation Systems

Improving energy and hydraulic performance of large-scale pressurized irrigation is now perceived as a very pressing need, after large budgets have been allocated into systems modernization. This paper tackles this priority area by developing a management oriented multi-step methodology, that integrates different existing models, to sector the system according to the pressure requirements of the hydrants, and to regulate the pumping station for i) a fixed and a variable pressure head control, and for ii) an enhanced performance. When applied to an on-demand system in the Sinistra Ofanto irrigation scheme of Foggia (Italy), this integrated approach showed potential for energy saving under the optimal scenario of 49 %, and noticeable improvement in the system performance in terms of hydrant pressure heads, as compared to the actual conditions. The monetary assessment demonstrates that the achieved energy saving amounts to 23,636 Euros per irrigation season, 45 % among which are due to sectoring.     

安阳县跃进渠灌区续建配套与节水改造方案及可行性探讨

跃进渠灌区运行年久失修,灌溉能力下降,不能满足农业生产的要求。本文针对灌区存在的问题,探讨灌区改造的可行性。     

A New Indicator for Unsteady Flow Analysis in Pressurized Irrigation Systems

Pressurized irrigation systems operating on-demand offer large flexibility to farmers for managing their irrigation practices. Within these systems, the fast moving water and the sudden closing of hydrants generates unsteady flow and may create a significant pressure variation in the pipes causing noise, vibration and, sometimes, also pipes’ collapse. The present study describes a simulation tool that was developed for the analysis of unsteady flow effects. A large number of configurations of hydrants simultaneously open has been used to reflect farmers’ behaviour. A new indicator, called Relative Pressure Variation (RPV), was proposed to evaluate the pressure variation occurring into the system in respect to the steady-state pressure. This is very relevant and can be used to identify pipes with potential risk of failure. In addition, an analysis with different gate-valves’ closing time was carried out. It demonstrated that closing time shorter than Tc?=?3 s may create dangerous pressures for the pipes.     

Optimal Operation of Pressurized Irrigation Networks with Several Supply Sources

The evolution of water distribution systems to pressurized networks has improved water use efficiency, but also significantly increased energy consumption. However, sustainable irrigated agriculture must be characterized by the reasonable and efficient use of both water and energy. Irrigation sectoring where farmers are organized in turns is one of the most effective measures to reduce energy use in irrigation water distribution networks. Previous methodologies developed for branched irrigation networks with one single source node have resulted in considerable energy savings. However, these methodologies were not suitable for networks with several water supply points. In this work, we develop an optimization methodology (WEBSOM) aimed at minimizing energy consumption and based on operational sectoring for networks with several source nodes. Using the NSGA-II multi-objective genetic algorithm, the optimal sectoring operation calendar that minimizes both energy consumption and pressure deficit is obtained. This methodology is tested in the irrigation district of Palos de la Frontera (Huelva, Spain) with three pumping stations, showing that potential annual energy savings of between 20 % and 29 % can be achieved, thus ensuring full pressure requirements in nearly all hydrants, along with the total satisfaction of irrigation requirements.     

Multi- Objective Optimal Design of on- Demand Pressurized Irrigation Networks

In the context of water as an economic good, from the use of water, one can derive a value, which can be affected by the reliability of supply. On-demand irrigation systems provide valuable water to skilled farmers who have the capacity to maximize economic value of water. In this study, simultaneous optimization of on-demand irrigation network layout and pipe sizes is considered taking into account both investment and annual energy costs. The optimization problem is formulated as a problem of searching for the upstream head value, which minimizes the total cost (investment and energy costs) of the system. The investment and annual energy costs are obtained in two separate phases. Max–Min ant system (MMAS) algorithm is used to obtain the minimum cost design considering layout and pipe diameters of the network simultaneously. Clement methodology is used to determine flow rates of pipelines at the peak period of irrigation requirements. The applicability of the proposed method is showed by re-designing a real world example from literature.     

潇河灌区渠系改造节水效益评析

潇河灌区经过近 5 0年的运行 ,渠系建筑物老化破损严重 ,灌溉水利用率极低。通过实施渠系改造工程 ,渠系水利用率由 0 .485提高到 0 .6 3,年节水量 70 4万m3,增加灌溉面积 8.6万亩次 ,节水效果明显 ,经济效益显著 ,保障了灌区的可持续发展     

洪山灌区渠系及建筑物老损评价研究

文中通过对洪山灌区节水改造设计中渠系及建筑物的老损程度评价的阐述，提出了一个全新的、较系统完善的评价办法，为灌区改造提供了一个良好的模式。     

宁夏东干渠冬季输水可行性初探

宁夏金积供水工程通过河东灌区东干渠输配水。随着供水量的日益增大，冬季进行补水已成为当务之急。为确保冬季渠道安全运行，解决渠道冬季运行过程中出现的问题，结合2010--2011年度运行情况进行了探讨，结论认为，冬季利用东干渠补水是可行的。     

杨柳溪水库灌区渠系建筑物优化设计

针对杨柳溪水库灌区地形地貌、地质条件较复杂,沿线部分渠段边坡稳定性较差、易形成高陡边坡等问题,经现场踏勘结合河渠交叉建筑物方案比选原则,综合考虑工程占地、施工难度及工程投资等因素,优选渠系整体布置方案和渠系建筑物结构形式.经水力计算、应力计算等论证分析,结果表明渠系建筑物结构、型式、过流能力和防洪特性等,均满足SL482-2011规范要求,优化设计方案具有较高的技术可行性和经济合理性.     

浑沙灌区渠道衬砌型式比选与设计

浑沙灌区是辽宁省的大型灌区,一直发挥着当地粮仓的作用。由于灌区渠道及建筑物老化失修,渠道漏水,渠道输水损失大,渠系水利用系数低,引起灌区供水不及时等一系列问题。本文通过对不同渠道衬砌形式进行方案比选,考虑工程量及工程造价等多方面因素,确定重力式浆砌石挡土墙为适合浑沙灌区的渠道衬砌型式,并对选定的结构型式进行设计和稳定性等验算。     

石津灌区渠道渗透率对地下水位的影响

通过收集石津灌区的水文地质资料,针对井渠结合灌区和纯井灌区的特点,建立了灌区的二维地下水动力学模型,分析了不同渠道衬砌率条件下的地下水位变化规律,以及渠道渗透率与地下水位之间的关系。结果表明:井渠结合灌区的地下水位随渠系水利用系数的增大而升高,当渠系水利用系数增大到一定程度时(本次研究为0.74),地下水位随渠系水利用系数的增大而下降;纯井灌区大部分区域地下水位与渠系水利用系数存在负相关关系,增大渠系水利用系数将降低该区域内地下水位;纯井灌区部分区域的地下水位与渠系水利用系数存在正相关关系,主要原因是附近渠灌区和井渠结合灌区对该地区的侧向补给。     

灌渠污水源截污工程施工技术

为解决水源还清问题,项目实施了丰台区灌渠污水源截污工程,对老城区存在许多淤泥的河道,甚至已经堵塞的河道,提出整改方案,实现河道清淤、截污管线以及污水处理.河道的生态环境问题得到解决,恢复了河道本来的面貌,让河道长治久清且恢复生态环境.     

人民胜利渠灌区水资源可持续利用综合评价

基于复合系统理论,利用分层和矩阵原理,采用模糊综合评价法,从水资源禀赋、水资源开发利用、社会经济和生态环境4个层次16个指标对人民胜利渠灌区水资源可持续利用状况进行综合评价。结果显示:灌区水资源可持续利用综合评分为50%频率年的大于75%频率年的,与水资源开发利用、社会经济和生态环境准则评分随不同年型的变化规律相一致,而水资源禀赋准则的变化规律为50%频率年的评分小于75%频率年的,说明人民胜利渠灌区水资源的开发利用处于可持续利用状态,具有连续性和持久性。     

改性PP纤维混凝土在灌区渠道护砌中的应用

我省是全国应用改性PP纤维进行渠道护砌较早的省份之一。在省水利厅的支持下，改性PP纤维已大量应用于渠道防渗等工程中。吉林省水利科学研究院做为吉林省水利厅下属的唯一的甲级科研单位，对改性PP纤维混凝土的性能做了大量的试验研究。为改性PP纤维混凝土在大中型灌区渠道防渗中的推广应用奠定了坚实的理论基础。本文着重介绍改性PP纤维混凝土在全省的应用情况、应用体会及应用前景。