水位流量关系分析中落差指数直接解算方法及其应用

受洪水涨落和回水顶托影响的水位流量关系一般为复杂的时序型绳套曲线，通常可用落差指数法作单值化处理，但由于落差指数法需经反复试算，给电算带来不便，提出了落差指数直接解算的数学模型，并应用于长江中游螺山站的水位流量关系分析。     

水位流量关系分析中落差指数的直接解算方法

受洪水涨落和回水顶托影响的水位流量关系一般为复杂的时序型绳套曲线，通常可用落差指数法作单值化处理。但由于落差指数法需经反复试算，给电算带来不便。本文提出了落差指数直接解算的数学模型，并应用于长江中游螺山站的水位流量关系分析。     

水位基面较差值对落差指数法流量单值化分析的影响探讨

落差指数法适用于断面基本稳定，受变动回水或变动回水及洪水涨落综合影响的测站。目前安徽省普遍应用落差指数法根据河道上下游水位站推求瞬时流量，实现流量软在线。当前在应用落差指数法时上下游水位站没有考虑基面较差值，本文以润河集站为例探讨基面较差值对落差指数法推求流量精度是否有影响。     

基于单值化分析方法的下巴沟水文站水位流量关系研究

下巴沟水文站是洮河流域重要的控制水文站,受流域气候、洪水涨落等因素影响,该站测得的水位-流量关系较为复杂。采用该水文站2010-2017年水位、流量实测资料,利用综合落差指数法对下巴沟水文站水位—流量关系进行单值化处理。通过分析,确定优选落差系数、落差指数等参数值,确定校正流量系数公式,获得该站水位-流量理论关系。结果表明,运用综合落差指数法所得的水位流量单值化结果的误差在相关规范要求之内,可应用于实际水文测量计算工作。     

落差指数法在西江梧州水文站应用初探

梧州水文站是珠江流域西江干流的重要控制站,水位流量关系复杂。为了解决流量实时在线监测和水文资料整编定线难题,满足不断拓宽水文服务领域的需求,采用落差指数法对梧州水文站水位流量关系进行单值化分析,对西江干流水情预警、水文分析评价具有十分重要的意义。结果表明：基于分年Z～q关系曲线和综合Z～q关系曲线采用落差指数法对梧州水文站水位流量关系进行单值化处理可满足水文资料整编规范要求;基于综合Z～q关系曲线的落差指数法易操作,使流量监测工作效率得到提高。     

基于综合落差指数法的监利（二）站水位流量关系单值化分析

监利(二)水文站位于监利河段,是长江中下游重要控制站。水位-流量关系主要受洪水涨落、断面冲淤、洞庭湖回水顶托等影响,水位-流量关系复杂,多为变形的绳套关系曲线,流量测次较多。选取2010～2017年监利(二)站实测水位和流量资料,选用新厂(二)和广兴洲水位站作为落差辅助站,采用综合落差指数法开展水位-流量关系单值化分析,将落差系数设为落差和监利(二)站水位的函数,并采用试错法确定落差指数。结果表明,水位-流量关系单值化分析结果较好,满足现行水文整编规范要求。     

落差指数法在桃溪水文站的应用

本文介绍了10多年来桃溪水文站采用落差指数法对其复杂的非单值水位流量关系进行单值化处理及历年综合单值化处理等情况，说明落差指数法概念明确、公式简单、使用方便、其较强的概括性和适用性，是对受变动回水、洪水涨落等综合因素影响或单一因素影响所形成的非单值水位流量关系单值化处理的有效方法。     

李家渡水文站水位流量单值化初探

试用落差指数法，使李家渡水文站水位流量呈单值关系，并用于推流验证，效果令人满意，其精度达到水文测验规范标准．     

南宁水文站水位流量关系单值化初探

介绍综合落差指数法的基本原理 ,并探讨其在南宁水文站的应用。综合落差指数法在处理受变动回水及洪水涨落混合影响的水位流量关系具有较强的适用性 ,效果较好 ,简便易行。     

史家口站水位流量关系单值化探讨

借用南方河网化地区的落差指数法,对史家口站生态补水期间的实测数据进行分析,探索对水位流量关系进行单值化处理的可能性.验证了以落差指数法为基础的单值化处理,在史家口站应用的可行性.可为同样受橡胶坝回水顶托影响的测站在进行水位流量关系单值化处理时提供参考.     

A Modified LAPSUS Model to Enhance the Effective Rainfall Estimation by SCS-CN Method

In this study, LAPSUS model is modified to enhance the effective rainfall estimation by SCS curve number method. The LAPSUS model calculates discharge based on effective rainfall and routs it towards lower neighbouring grid cells following the multiple flow direction principle. Then, the sediment transport capacity and sediment transport rate are calculated in each grid cell. Finally, erosion or sedimentation is calculated by comparing the sediment transport rate with the sediment already in the transport of each grid cell. The amount of rainfall, curve number, convergence factor, discharge exponent, slope exponent, erodibility factor, and sedimentation ability factor are inputted to the application page of the modified model that was created in the C⁺⁺ programming. The outputs of the model are runoff and erosion maps in ASCII format. Evaluating performance of the modified model showed a high accuracy of its results. The value of the coefficient of determination (R²) calculated 0.99 for runoff and 0.97 for erosion. The Nash-Sutcliffe efficiency was 0.96 for runoff and 0.97 for erosion. The value of the precision index calculated 0.81 for both runoff and erosion. Also, the nRMSE calculated 3% for both runoff and erosion. The result showed that the modified model capable to estimate the runoff and erosion on a landscape in a micro sub-catchment scale.     

平底抛物线形复合渠道水力最佳断面及实用经济断面统一设计方法

大中型渠道常采用平底抛物线形复合渠道断面形式进行设计,但任意幂律指数的平底抛物线形复合渠道的湿周计算理论上无解析解,致使任意幂律指数的平底抛物线形复合渠道的水力最佳断面及实用经济断面无统一设计方法。现有的文献,仅研究了给定幂律指数情况下的平底抛物线形复合渠道断面,并没进行全局范围内的研究。本文首先采用高斯超几何函数给出了任意幂律指数的平底抛物线形复合渠道湿周的解析计算式,再以水面宽度与水深的比率、渠部底宽与水深的比率及水深为变量,利用拉格朗日乘数法建立了平底抛物线形复合渠道的水力最佳断面求解方程;进一步根据实用经济断面与水力最佳断面的关系建立了平底抛物线形复合渠道的实用经济断面求解方程。本文不仅给出了全范围内连续变化的任意幂律指数的平底抛物线形复合渠道的水力最佳断面及实用经济断面统一设计方法,直接计算公式及数据表格,而且得到了平底抛物线形复合渠道的水力最佳断面中的最优幂律指数为3,从而取得全局水力最佳断面。本文结果可供大中型渠道规划设计参考应用。     

水文测验与水文资料整编方法的研究

本文应用抵偿河长原理，以梨树水文站为研究对象，用水位后移法对水位流量关系进行优化，极大简化了该站水文测验测次及水位流量关系，提高了水文资料整编的精度     

“网河”非稳定流模型在洪泛区洪流演进中的应用

将宽阔的溃口洪水行进范围概化成由河道水塘和联系河道组成的网河,用一维非恒定流方程组来描述主要的水充运动状态,通过简化和变换,改写成统一的四点线性隐式有限差的方程组形式,再用双消除法求解,全部计算在微机上实现,参数用实测资料率定,成果具有较好的精度,在一定程度上反映出横水流方向的水位流量变化,为防洪水利计算开辟一条新的途径。     

Rating Curve Development at Ungauged River Sites using Variable Parameter Muskingum Discharge Routing Method

A physically based simplified discharge routing method, namely, the variable parameter Muskingum discharge-hydrograph (VPMD) routing method, having the capability of estimating the stage hydrographs simultaneously in channels with floodplains is presented herein. The upstream discharge hydrograph is routed using this VPMD method in different two-stage symmetrical trapezoidal compound cross section channel reaches. The performance of the VPMD method is evaluated by numerical experiments using the benchmark MIKE11 hydrodynamic model and the field data of the Tiber River in central Italy. The proposed method is capable of accurately routing the discharge hydrographs, corresponding stage hydrographs and synthesizing the normal rating curves at any downstream ungauged river site which is not affected by any downstream effects. This study can be helpful for various planning and management of river water resources in both the diagnostic and prognostic modes.     

线性扰动模型在长江中下游洪水预报中的应用

采用1984年引进的线性扰动模型对于洪水涨落缓慢的长江中下游进行了洪水连续预报的研究,并以1991年为例,对长江中下游的湖口站、大通站和南京站作出洪水连续预报,检验结果表明,从峰、量方面误差均达到《规范》要求。如利用上游站的预报值直接作为下游站输入系列,将增加预见期,且在处理模型中的参数方面,优化容易、主观性少,操作简单。     

河道洪水实时预报模型及在寸滩—螺山河段的应用

采用水力学和水文学相结合的方法，根据河道非恒定流的圣维南方程组，建立了河道洪水相应涨至预报模型和扩散波洪水预报模型，既可预报流量，又可预报水位。在模型的实时校正技术中，采用了具有时变遗忘因子的递推最小二乘实时校正算法，提高了参数实时跟踪能力和辨识精度。相应涨差实时预报模型和扩散波实时预报模型在寸滩－螺山河段上的应用均获得较好的效果。     

A Piecewise Grey System Model for Study the Effects of Anthropogenic Activities on Karst Hydrological Processes

Sustainable groundwater development must rely on a good understanding of hydrological processes, especially under effects of anthropogenic activities. This paper develops a piecewise analysis based on grey system model for study effects of anthropogenic activities on hydrological processes. The time series of precipitation and spring discharge were segmented into three time periods depending on whether variations are due to climate variation: the predevelopment stage, the transition stage, and the new equilibrium stage. Then we modeled hydrological process of the predevelopment stage and new equilibrium stage by the grey system model. By comparing the model results, we can quantify the effects of human activities on hydrological processes. We applied the model to Liulin Springs China. The results indicated that the hydraulic response time of the spring discharge to precipitation from the predevelopment stage to the new equilibrium stage, ranges from less than 1 year to up to 4 years. The results revealed that human activities slow the groundwater flow. GM (1,N) models of Liulin Springs discharge showed that the driving coefficients of precipitation to the spring discharge decreased from 0.012272 in the predevelopment stage to 0.007753 in the new equilibrium stage, which means that groundwater recharge ability has reduced about 36.82 %. Human activities in Liulin Springs have drastically changed the groundwater system. Piecewise grey system model is a robust method for hydrological process simulation.     

Real-time flood forecasting of Huai River with flood diversion and retarding areas

A combination of the rainfall-runoff module of the Xin’anjiang model, the Muskingum routing method, the water stage simulating hydrologic method, the diffusion wave nonlinear water stage method, and the real-time error correction method is applied to the real-time flood forecasting and regulation of the Huai River with flood diversion and retarding areas. The Xin’anjiang model is used to forecast the flood discharge hydrograph of the upstream and tributary. The flood routing of the main channel and flood diversion areas is based on the Muskingum method. The water stage of the downstream boundary condition is calculated with the water stage simulating hydrologic method and the water stages of each cross section are calculated from downstream to upstream with the diffusion wave nonlinear water stage method. The input flood discharge hydrograph from the main channel to the flood diversion area is estimated with the fixed split ratio of the main channel discharge. The flood flow inside the flood retarding area is calculated as a reservoir with the water balance method. The faded-memory forgetting factor least square of error series is used as the real-time error correction method for forecasting discharge and water stage. As an example, the combined models were applied to flood forecasting and regulation of the upper reaches of the Huai River above Lutaizi during the 2007 flood season. The forecast achieves a high accuracy and the results show that the combined models provide a scientific way of flood forecasting and regulation for a complex watershed with flood diversion and retarding areas.