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1.
可利用水资源量正逆向联合计算方法   总被引:1,自引:0,他引:1  
基于可持续利用考虑,提出以区域水环境容量可承受用水量作为可利用水资源量的逆向计算方法,并与传统的以区域水资源总量为基础的正向计算方法联合。对该计算方法的影响因素:洪水弃水量、河道需水量、水质达标率及水环境容量和单位耗水排污量分别进行了分析。应用该方法分别计算了闽江上游富屯溪流域、沙溪流域和闽江干流下游流域的可利用水资源量。结果表明,下游流域可利用水资源量宜取正向计算方法结果,上游流域2种计算方法结果相差不大,但会出现逆向计算方法结果小于正向计算方法结果的情况。相比于传统的正向计算方法,采用正逆向结合计算方法即考虑了工程调蓄、河道需水及水质状况等因素,也保证了流域水资源的可持续利用。  相似文献   

2.
由于现有的水电站下游水位预测方法计算误差较大,选择葛洲坝水电站为研究对象,提出一种新的电站在不弃水情况下的下游水位变化过程预测方法。该方法基于BP神经网络算法,利用水电站监控数据实现电站下游水位的高精度预测,满足电站实时调度需求。对比现有的水位流量曲线查值法和非恒定流经验公式法,该方法有如下优势:①无需采用出库流量进行预测,避免了流量计算误差的影响;②建模过程中考虑了下游水位变化"后效性"影响,大幅提升水电站调峰时的预测精度;③可直接计算下游水位变化过程,计算结果稳定,精度更高,尤其在非弃水期葛洲坝水电站大调峰工况下,预测精度明显提高。  相似文献   

3.
Aiming at resolving the grid problems caused by the inconsistent resolution requirements when simulating overland flows using the 2D shallow water equations, a novel grid generation method based on multi-resolution data fusion is developed in this work. This method is able to not only reduce the computational burden associated with uniform structured grids but also ensure the simulation accuracy of the hydrodynamic model by reproducing the so-called small-scale effect. The efficiency of the method is assessed using different cases. Theoretical and laboratory cases demonstrate that fused non-uniform structured grids can reproduce hydrographs without appreciable accuracy losses. In addition, a high simulation accuracy (NRMSE ≤ 10.40 %, R2 ≥ 0.87) is achieved in the simulation of a real flood event. The performance of this method is very promising in terms of the large-scale flood simulation accuracy, and it significantly reduces the data requirements and computational burden with globally fine uniform grids.  相似文献   

4.
本文就地下输水管道的基础要求,对公主岭布不同地质情况的地基土壤特性进行分析论述,并提出相应的处理方法和处理意见。  相似文献   

5.
介绍了破产理论在区域水量分配问题中的应用。分析了传统破产理论在水量分配问题中的有效性和局限性,考虑配水单位水资源丰富程度、用水效率和最低供水保障率3个因素,对破产理论传统的分配规则进行优化改进,并实例应用于广东省东江流域各地市的水资源竞争性分配中。结果表明:(1)改进后的分配规则能综合考虑各分水单位水资源丰富程度和用水效率等各方面因素,合理排列分水单位的配水优先等级,确保高优先级单位水量供给,同时保证低优先级单位的最低供水标准;(2)面对未来不确定性来水条件,当可供水总量逐渐减少时,不同配水优先级单位具有不同的反应速率,高配水优先等级的配水单位其供水满足率的下降速率更趋缓慢,进一步体现了其优先配水地位。改进后的破产理论规则应用于区域水量分配中能够得到合理的分配结果,而且能根据问题的不同要求进行规则调整,极具灵活性,可以推广应用于其他地区。  相似文献   

6.
Australian experience at five research sites where stormwater and reclaimed water have been stored in aquifers prior to reuse, have yielded valuable information about water treatment processes in anaerobic and aerobic aquifers. One of these sites is the stormwater to potable water ASTR project at the City of Salisbury, a demonstration project within the broader EC project 'RECLAIM WATER'. A framework for characterising the effectiveness of such treatment for selected organic chemicals, natural organic matter, and pathogens is being developed for inclusion in new Australian Guidelines for Management of Aquifer Recharge. The combination of pre-treatments (including passive systems such as reed beds) and aquifer treatment effectiveness in relation to source waters and intended uses of recovered water will be described. Advantages and disadvantages of various types of pre-treatments in relation to effectiveness and sustainability of managed aquifer recharge will be discussed taking account of aquifer characteristics. These observations will be consolidated into a draft set of principles to assist in selection of engineered treatments compatible with passive treatment in aquifers.  相似文献   

7.
区域水安全系统评价新方法探析   总被引:2,自引:0,他引:2       下载免费PDF全文
基于可持续发展理论的压力-状态-响应概念框架,探讨了区域水安全评价指标体系的建立,并改进已有的遗传投影寻踪评价方法,构造了基于多目标决策理想点法(TOPSIS)的相对贴近度概念的投影目标函数,利用蒙特卡罗方法产生的大样本数据,建立了一种适合于区域水安全系统评价的新方法(模型)——遗传投影寻踪-理想点插值模型(GPP-IPIM),并将其成功地应用于我国广东省北江下游及其三角洲地区水安全系统评价,评价结果具有直观性、合理性和通用性。对评价结果基于不确定性分析的敏感性进行分析,结果表明GPP-IPIM是一种稳定、有效的区域水安全系统评价方法,并可应用于各种水资源系统评价问题。  相似文献   

8.
一种新的水面线计算方法   总被引:7,自引:0,他引:7       下载免费PDF全文
在现行水面线试算模型的基础上,改造得出一种新的水面线试算模型,解决了由上游控制水位向下直接试算推求河道水面线的问题,同时还能处理传统方法所不能直接解决的一些实际问题.在江西抚河上应用该方法进行了计算,结果表明该方法是合理和可信的.  相似文献   

9.
科学客观地预测城市生活需水量,合理规划水资源的配置,是城市发展的需要. 本文运用GM(1,1)模型和一元线性回归模型相结合的组合模型对城市生活需水量进行预测,结果表明,组合预测综合考虑了各种因素的影响,能够提高需水量的预测精度,为水资源合理规划提供了科学决策依据.  相似文献   

10.
本文将分步有限元的计算方法引入到浅水方程组的求解中。该方法起源于Taylor-Ga!erkin(T-G)方法,但数值稳定性优于T-G法并具有三阶精度。由于计算中没有引入高阶的空间导数项,实现起来比Taylor-Galerkin方法简单,适用于非线性和多维问题的求解。计算模型中包含了零方程和双方程的紊流模型,可以根据需要选择。文中详细介绍了初始和边界条件的取法,并通过五个算例验证了计算模型的可靠性。  相似文献   

11.
深水时域格林函数的实用数值计算   总被引:2,自引:0,他引:2  
如何精确而又快速地计算时域格林函数及其导数是求解船舶水动力问题的关键。论文基于Bessel函数的性质推导了深水格林函数及其导数所满足的常微分方程,提出了结合求解常微分方程的节点制表、节点间插值的快速计算格林函数的方法。数值计算表明该计算方法克服前人节点制表节点间插值计算方法的缺点,提高了格林函数的计算效率和数值精度。  相似文献   

12.
肖华  邰东国  张湘隆 《人民长江》2011,42(23):43-46
针对水库生态与环境需水量牵涉面广的问题,在分析水库生态与环境需水量内涵的基础上,提出了水库生态库容与环境库容的计算原则与量化计算方法.水库生态与环境需水量应遵循生态优先与多功能兼容、多指标分等级控制与最不利指标调控相结合、时间动态平衡与空间均衡协调的原则.根据拟定的计算原则和计算方法,分析计算了广东省合水水库全年各时期...  相似文献   

13.
A combined system using nano MgO and nanofiltration (NF) membrane was established to purify polluted water in this experiment. The turbidity, permanganate index, UVA254, colony counts and the concentrations of NO3-, NO2-, NH4+, Fe, Mn and Mg of the effluents from each unit of this combined system were measured to investigate the pollutant removal of this system. Based on the results obtained, the combined nano MgO-NF system could efficiently remove many kinds of pollutants in this experiment, including organic matter, nitrogen species, heavy metals, suspended solids and bacteria. And the effluents could meet the standard of drinking water. Furthermore, increasing the nano MgO dosage could not elevate the removal ratio of the pollutants, but only increase the Mg content of the effluent. Thus, 0.05 g L(-1) of nano MgO may be a suitable dosage for 2,000 L of polluted water treatment. Also, the operating pressure of NF membrane had no significant effect on pollutant removal when the operating pressure of NF membrane was increased from 0.3 to 0.9 MPa.  相似文献   

14.
15.
A novel 3-D model for the water cresting in horizontal wells   总被引:1,自引:1,他引:0  
In the presence of bottom water, a drop in the reservoir pressure due to fluid production causes the aquifer water to expand and to flow into the reservoir. Therefore, hydrocarbon production from a well is limited by the critical flow rate. The main purpose of this study is to investigate the breakthrough time and the critical rate by using a novel 3-D horizontal well model. Based on the hypothesis that the horizontal well is located in any position of a circular reservoir with no-flow boundary on the top of the reservoir and constant pressure boundary at the bottom, the horizontal well has been regarded as an infinite conductivity line sink and then a 3-D steady-state flow model of the horizontal well is set up. A point sink pressure solution can be obtained with the Fourier transform. The result of the pressure distribution of the uniform flux horizontal well can be presented by means of the principle of superposition. According to the stable water cresting theory, this study confirms the stable height of water cresting and the critical rate. Meanwhile, it can re-confirm the breakthrough time at a specific rate. The output of a comparison between this 3-D model and the reservoir numerical simulator (Eclipse) shows the method presented here can be applied to investigate the behavior of a water cresting and to predict the breakthrough time at the bottom water driver reservoir.  相似文献   

16.
针对混凝土坝变形监测数据缺失使大坝服役状态分析困难甚至引起误判的问题,基于聚类和面板数据理论,提出了一种考虑时间和截面两种维度的混凝土坝变形监测缺失数据处理新方法.该方法兼顾了影响大坝变形的共同因素和特异因素,与传统方法相比,能更加全面地反映荷载和非荷载因素对大坝结构性能的影响,对大坝变形监测缺失数据的处理更加有效.某...  相似文献   

17.
利用DEM提取数字水系的过程分为填洼、流向计算、汇流累积量计算和设定阈值提取水系,其中以填洼和计算各单元的汇流累积量最为费时。相比与Jenson和Domingue(JD)、Planchon和Darboux(MV)填洼算法,L.Wang和H.Liu(WL)填洼算法具有原理简单、运行速度快等特点。但是,WL算法未对平区高程进行修正,增加了后续相关算法的复杂度。本文通过将JD和MV算法中的微小高程增量引入WL算法,建立改进的WL算法,可以有效地解决该问题。在汇流累积量的计算过程中,受WL填洼算法思想的影响,构建了逆向WL汇流累积量算法,该算法一改传统的流向追踪思想,通过对填洼后DEM进行升序排序,可逐步对每一栅格进行计算。该算法原理简单,易于实现,对单流向和多流向方法均具有很强的适应性。利用SRTM、GDEM源数据进行了示例计算,并将结果与ARC/INFO软件结果进行了对比,结果表明该方法合理、准确。  相似文献   

18.
张静  于金宝  熊伶  崔福义 《给水排水》2021,47(8):167-176
高锰酸钾氧化技术可有效去除水中微量有机污染物、降低色/嗅和抑制藻类繁殖等,且该技术选择性良好,氧化过程不会产生卤代副产物.但高锰酸钾氧化能力温和,对部分难降解有机物处理效果不佳,投量过高时易造成出水色度和锰超标.故学者们将高锰酸钾氧化与配体、紫外、亚硫酸(氢)盐、超声等联用,通过诱导产生中间态锰或自由基提高其氧化效能,...  相似文献   

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20.
基于公平和效率原则,构建文山州水量分配指标体系和水量分配投影寻踪(PP)模型。针对PP模型最佳投影方向难以确定的不足,利用新型蝙蝠算法(NBA)搜寻PP模型最佳投影方向,构建NBA-PP水量分配模型对文山州8县(市)水量进行分配。通过5个典型测试函数对NBA算法进行仿真验证,仿真结果与基本蝙蝠算法(BA)、人工蜂群算法(ABC)、布谷鸟搜索(CS)算法和差分进化算法(DE)进行对比。结果表明:通过引入生境选择策略及自适应补偿回声多普勒效应机制的NBA算法能有效平衡全局搜索和局部开发能力,寻优效果优于DE、CS、ABC和BA算法,具有较快的收敛速度、较高的寻优精度和较好的收敛稳定性与收敛可靠性;NBA-PP模型水量分配结果较目前分类权重法分配结果更科学、客观。  相似文献   

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