输水工程取水头部水流特性三维数值模拟研究

首先阐述三维紊流的计算方法,针对输水工程进水口水流特性,采用标准k-ε模型对三维水流运动进行计算,选取VOF法对自由表面进行处理,利用有限体积法对计算区域进行离散化,并采用无滑移的固壁边界条件,模拟进水口水流的复杂流动状态,并将数值模拟的结果与试验资料进行详细比对,验证数学模型的可靠性,在进水口工程设计研究中有较大参考价值。     

大峡水电站全厂水位测量装置

上下游水位及拦污栅压差是水电站的重要数据,因设备老化、抗干扰能力差、维护困难等各种原因,我们对全厂水位及拦污栅压差测量装置进行改造。改造方案采用静压式传感器来实现监测水的深度,将水位移动量转换成4～20mA的电信号输出。改造后的装置在实际使用中工作稳定,在监视报警、综合计算等各方面满足电站对这些信号的要求,取得了很好的效果。     

Coupled optimization-simulation water quality model for regional water quality management

The objective pursued in water quality management is to secure water qualities such that marginal cost of the cleaning water equals the accuring marginal benefits. It is the purpose of this paper to show how the methods of system analysis may be used to plan more economical new pollution control facilities or how to upgrade existing systems. The particular problem investigated is the following: Given a region with a number of industries and/or municipalities, where should one build treatment plants and will be necessary levels that total regional cost of waste water treatment is minimum. To approach these problems, a stream water quality simulation is linked with a treatment cost minimization model in order to capitalize on the unique adventage of each in managing river basin water quality.     

Hybrid water treatment cost prediction model for raw water intake optimization

In order to reduce the total cost of a dual source drinking water treatment plant operation, a comprehensive hybrid prediction model was built to estimate the necessary chemicals dosage and pumping energy costs for alternative source selection scenarios. Correlations between the water quality parameters and the required treatment chemicals were estimated using historical data and the expected pH variations associated with each chemical addition, which was based on the Caldwell–Lawrence diagram. The pumping energy costs were also estimated using a data-driven approach that was based on historical plant data. The research has practical implications for water treatment operators seeking to minimize plant operational costs through selecting raw water intake volumes for their treatment plant based on multiple source options and offtake tower gate levels. Future research seeks to better link current and future water treatment dosage cost predictions directly to water quality measurements taken from vertical profiling systems.     

面向水域保护的水域信息管理平台建设研究

为加强水域保护,实现水域管理的信息化和规范化,提高水域保护的效率与科学水平,设计并开发基于WebGIS的水域信息管理平台。以镇江市为研究区域,从水域管理和规划的双重需求出发,整合数据资源构建水域本底数据库、完善水域档案资料,在此基础上,采用框架结构设计和面向对象相结合的技术,设计并实现水域一张图管理、水域动态监测、洪涝分析、侵占补偿、查询统计、变化分析、档案管理和权限设置等功能模块。水域信息管理平台的应用一方面可以辅助政府工作,有效提升河湖水域管理与保护工作水平,另一方面可为水域保护与规划、城市排水系统建设及城市用地规划等相关工作提供数据服务、技术支撑和科学化测评手段,同时可为其他城市水域保护信息化平台建设提供参考。     

SD-GIS-based temporal-spatial simulation of water quality in sudden water pollution accidents

System dynamics (SD) is well suited for studying dynamic nonlinear complex systems. In this paper, SD is applied to a rapid-onset water pollution accident using a 1-D water quality model and a conceptual GIS-SD framework is constructed to simulate the temporal-spatial changes of pollutant concentration. Based on the component GIS and the SD model, a prototype system of water quality simulation in water pollution accidents is developed. The data collected on the spot in the Songhua River water pollution accident in November 2005 were used for model parameter calibration and model validation. The results showed that: (1) the constructed model could simulate the changes of nitrobenzene concentration with time in the Songhua River water pollution accident, especially during the peak concentration and at the arrival time of peak concentration, and that the simulated values and the on-the-spot monitored values corresponded with each other well; (2) the scenario simulation could be made by adjusting parameters u (longitudinal current velocity), E (longitudinal diffusion coefficient), and k (decay rate coefficient). Such a model can provide decision makers with quantitative information to optimize related emergency response measures.     

Continuous-time and discrete-time design of water flow and water level regulators

A thorough analysis of the water flow and water level control problems arising in several industrial systems is provided using classical and sampled data linear control theory. The analysis is based on simplified linear models of the processes under control. Resulting design rules enable engineers to choose the correct controller both in the continuous-time and in the discrete-time case. A practical application example is included.     

以用水工艺过程为主题高效用水管理

根据工业用水的特点,以平台为基础,结合软件信息技术,以用水工艺过程为主题,搭建用水管理系统。对每一项用水工艺环节进行信息处理和数据分析,发掘节水潜力。对各用水工艺过程科学管理,制订合理适用的用水定额和用水指标。制订用水工艺过程的主题,对每一项用水环节深入分析,部分带动整体,从而实现企业工业的高效的用水管理。     

钢铁工业用水过程可视化及节水评价

钢铁工业是现代社会扩大再生产的基础,在工业领域中是用水大户,在当下水资源供需矛盾突出的情况下对区域水资源短缺及行业用水竞争产生不小挑战。解决问题的思路是深入剖析钢铁工业的用水过程,以精细化的节水评价挖掘各环节节水潜力。通过组件和知识图将钢铁工业用水情况过程化表达,涉及来水、用水、排水等过程,最终在综合集成平台上展现。具体以焦化工艺用水过程为例,介绍知识图的绘制和节水评价的实现。结果表明,可视化有利于钢铁工业用水过程化管理,在此基础上的节水评价是真实可信的,可为决策服务,从而达到强监管的目的。     

基于水流分割的石油钻井水流异常检测

通过对钻井管道水流的智能监控技术实现,可以解决石油钻井污染气体的自动监测问题,最大程度的减少人工监测成本;但是依然有以下几个难点需要攻克:(1)传统的特征提取方式不能描述水流形态的变化过程;(2)因为异常情况发生的概率很低,所以异常样本稀少,全监督的方法不再适用;为解决特征提取问题,提出了一种基于图像分割的新特征特提取方式——形态流,形态流可以从时序上描述水流形态的变化;另一方面,为克服异常样本稀少的问题,通过无监督的方式——多元高斯建模,来判别水流数据是否正常;实验表明在水流异常数据检测任务中算法检测精度达到了93.6%,在使用GPU并行加速处理时可达到28帧每秒的处理速度,能够准确地检测出水流数据中的异常数据帧。     

A weighted normalized difference water index for water extraction using Landsat imagery

Water extraction is one of challenging topics in studies on remote-sensing applications. Spectral profiles and experiments indicate that existing water indices often misclassified turbid water, small waterbodies, and some land features in a shadow area. In this study, a new water index called weighted normalized difference water index (WNDWI) was proposed to reduce those errors and improve the mapping accuracy of waterbodies by using Landsat imagery. To test the performance of the newly proposed water index, two test sites (Tampa Bay, FL, USA and Xiangshan Harbour, Zhejiang, China) were selected and the performances of three existing water indices including the normalized difference water index (NDWI), the modified NDWI (MNDWI), and the automated water extraction index (AWEI) were compared with that of the WNDWI. In addition, a default threshold 0 and automatically thresholding methods including Otsu threshold method and multiple thresholds identified by valley points in a histogram curve were tested to determine an optimal threshold that can be used to separate water and non-water features from grey images created by the four water indices. The experimental results indicate that the overall accuracies (OAs) created with WNDWI were all higher than those created with the three existing water indices: NDWI, MNDWI, and AWEI in both sites. Moreover, the results thresholded by 0 owned or shared the highest OAs with the results segmented by some of non-zero thresholds obtained from Otsu method and multiple thresholds method. Therefore, using an appropriate threshold, the proposed method could extract waterbodies from Landsat TM imagery with a high accuracy.     

Safe river water: A ubiquitous and collaborative water quality monitoring solution

Water quality is vital to human life and economy. However, one sixth of the world’s population suffers from lack of safe drinking and domestic water. Aiming to improve the capability of predicting and responding to river pollution disasters, this project collaborated with local offices of Chinese National Bureau of Water Resource to explore new solutions to coping with the ever-growing threat of river water pollution. We presented a distributed data analysis algorithm, Infinitesimal Dividing and Analysis, to efficiently locate pollution sources with data gathered from a ubiquitous wired/wireless sensor network. We elaborate on a π-calculus based paradigm to enhance collaboration and interaction among individual monitoring stations. Based on these two enabling technologies, we applied our framework to water quality monitoring at two carefully chosen sites in China.     

Dynamic analysis of a water–soil–pore water coupling system

This paper explores the possible integration of the dynamic analyses of interaction of pore fluid flow and porous structure. The generalized fluid–structure interaction (FSI) algorithm in ADINA is applied for seismic analysis of a reservoir–earth dam–foundation system. In the given numerical example, water in the reservoir interacts with the earth dam on the upstream slope of the dam, and the foundation at the reservoir bottom. Pore water couples with soil particles throughout the earth dam and foundation. The reservoir water is modeled using both the Navier–Stokes equation based fluid element and the subsonic potential based fluid element. In the coupled analysis, hydrodynamic pressures and velocities are presented in the reservoir zone, while displacements, pore pressures and stresses are given for the earth dam and foundation domains at any earthquake time. The generalized FSI model is of great significance in performing soil liquefaction analysis if an appropriate soil plasticity model is employed in accounting for cyclic behavior of soils.     

Remote sensing of water quality in active to inactive cooling water reservoirs

Abstract

Airborne Daedalus DS-1260 MSS data were acquired over three water cooling reservoirs (active to inactive, large (1068 ha) to small (68-6 ha)) concurrent with field data collection to map the distribution of the water quality as related to the trophic state within each reservoir. Water characteristics, including algal pigments, total suspended particles, as well as dissolved and particulate organic matter, were obtained at 31 sites. These water quality measurements were evaluated in terms of their importance in explaining water phenomena observed by using remote sensing reflectance images. Measurements that exhibited unique variances were related to remote sensing data using a statistical methodology to identify relations explaining the greatest amount of variance for each water variable. This approach resulted in predictor equations explaining 91 per cent of the chlorophyll-a variance, 91 per cent of the total suspended particles variance, and 98 per cent of a Trophic State Index variance based on the depth of light penetration. Further, remotely-sensed thermal data explained 88 per cent of the measured surface water temperature variance. These relations were used to produce maps depicting the quantitative distribution of these water quality variables and the bulk near-surface water temperature distribution within the active water cooling reservoir. The two-water cooling reservoirs not affected by thermal inflows were characterized by water containing very low and uniform concentrations of all water property measures. Conversely, the thermally active reservoir was characterized by higher and more variable water property concentrations; there was a spatial covariation between decreases in the bulk near-surface water temperature and increases in almost all water quality indicators.     

用水成本不确定条件下生态工业园区全局用水网络综合研究

提出并建立园区层面全局用水网络的超结构模型,运用数学规划法,以用水成本最小化为目标,确定新鲜水用量及其对应的全局用水网络结构.以新鲜水价格变化为驱动力,提出新鲜水价格区间与其对应的用水网络综合的关系.以某园区为实例,当水价分别在0～0.7,0.7～2.58和大于2.58美元/10～3gal区间时,对应的新鲜用量分别为1829×103gaVd,529×10～3gal/d和0 gal/d.随着新鲜水价格的增加,新鲜水的用量会逐渐减少,相应的再生水处理单元数会逐渐增加.     

节水减排优化水网络系统的集成

节水减排是当前一个世界性的大课题，对我国而言更为紧迫。本文先介绍了这方面国内外的形势，然后论述了化工石化企业水网络系统的发展沿革。本文主要部分重点介绍了两种水系统优化集成方法：水夹点分析法及混合整数规划MINLP法。指出用这种过程系统工程方法来优化水网络系统的配置，不论对新厂设计还是老厂节水减排，均有十分显著的效益。     

中间水道水系统集成技术在催化剂厂的应用

具有中间水道的水集成技术所设计的用水网络有良好的操作柔性。本文采用该技术对某催化剂厂的用水系统进行了节水改造，运用调优技术，构造出实用的用水网络，取得了良好的节水效果。     

谐振式水位传感器

介绍了谐振式水位传感器的新型传感原理 ,传感器的结构 ,数字振荡电路的特点 .阐述了水位与频率的对应关系。     

交互式实时水面渲热

介绍了一种利用可编程图形硬件来实现水面实时渲染的方法。该渲染过程分为两个阶段,即水面建模和光照实现。通过当前图形硬件新提供的顶点纹理技术来对水面进行建模,并结合环境纹理映射技术和二维纹理映射技术实现了水面上的反射与折射等光照现象。实验证明,该方法大大提高了渲染速度,增强了水面渲染的交互性和实时性。