This paper describes a flood routing method applied in an ungauged basin, utilizing the Muskingum model with variable parameters of wave travel time K and weight coefficient of discharge x based on the physical charac...This paper describes a flood routing method applied in an ungauged basin, utilizing the Muskingum model with variable parameters of wave travel time K and weight coefficient of discharge x based on the physical characteristics of the river reach and flood, including the reach slope, length, width, and flood discharge. Three formulas for estimating parameters of wide rectangular, triangular, and parabolic cross sections are proposed. The influence of the flood on channel flow routing parameters is taken into account. The HEC-HMS hydrological model and the geospatial hydrologic analysis module HEC-GeoHMS were used to extract channel or watershed characteristics and to divide sub-basins. In addition, the initial and constant-rate method, user synthetic unit hydrograph method, and exponential recession method were used to estimate runoff volumes, the direct runoff hydrograph, and the baseflow hydrograph, respectively. The Muskingum model with variable parameters was then applied in the Louzigou Basin in Henan Province of China, and of the results, the percentages of flood events with a relative error of peak discharge less than 20% and runoff volume less than 10% are both 100%. They also show that the percentages of flood events with coefficients of determination greater than 0.8 are 83.33%, 91.67%, and 87.5%, respectively, for rectangular, triangular, and parabolic cross sections in 24 flood events. Therefore, this method is applicable to ungauged basins.展开更多
The parameter X of the Muskingum method is a physical parameter that reflects the flood peak attenuation and hydrograph shape flattening of a diffusion wave in motion. In this paper, the historic process that hydrolog...The parameter X of the Muskingum method is a physical parameter that reflects the flood peak attenuation and hydrograph shape flattening of a diffusion wave in motion. In this paper, the historic process that hydrologists have undergone to find a physical explanation of this parameter is briefly discussed. Based on the fact that the Muskingum method is the second-order accuracy difference solution to the diffusion wave equation, its numerical stability condition is analyzed, and a conclusion is drawn： X ≤ 0.5 is the uniform condition satisfying the demands for its physical meaning and numerical stability. It is also pointed out that the methods that regard the sum of squares of differences between the calculated and observed discharges or stages as the objective function and the routing coefficients C0, C1 and C2 of the Muskingum method as the optimization parameters cannot guarantee the physical meaning of X.展开更多
由于沅水水系五强溪水库流域面积大,流量控制站少,且洪水进入库区后,洪水波的传播方式变化较大,因此五强溪水库近坝区的洪水预报难度大。为提高五强溪库区洪水预报精度,采用XAJ-DCH模型(Xin′anjiang Digital Channel Model)对近坝区201...由于沅水水系五强溪水库流域面积大,流量控制站少,且洪水进入库区后,洪水波的传播方式变化较大,因此五强溪水库近坝区的洪水预报难度大。为提高五强溪库区洪水预报精度,采用XAJ-DCH模型(Xin′anjiang Digital Channel Model)对近坝区2016~2020年间13场洪水进行模拟,模型河道汇流分别采用了非线性水库法和马斯京根法,根据两种汇流方法的特点制定了两种不同的洪水预报方案。模拟结果表明:XAJ-DCH模型中两种河道演算方法均表现良好且简单实用,13场洪水的确定性系数基本位于0.7以上。非线性水库方法相比于马斯京根法考虑了河段断面情况以及水力特性,能够体现洪水运动的时空变化,且只需要率定河道糙率,其他参数如河道坡降、河宽以及河段长均可根据数字高程模型进行估计;马斯京根法需要率定4个河道参数,但马斯京根法模拟结果相比于非线性水库方法稍好。研究成果可为科学有效开展库区洪水预报、提高预报精度提供参考。展开更多
基金supported by the Technological Fund Item of China University of Mining and Technology (Grant No. OF4533)the Key Research Project of the Water Resources Department of Henan Province
文摘This paper describes a flood routing method applied in an ungauged basin, utilizing the Muskingum model with variable parameters of wave travel time K and weight coefficient of discharge x based on the physical characteristics of the river reach and flood, including the reach slope, length, width, and flood discharge. Three formulas for estimating parameters of wide rectangular, triangular, and parabolic cross sections are proposed. The influence of the flood on channel flow routing parameters is taken into account. The HEC-HMS hydrological model and the geospatial hydrologic analysis module HEC-GeoHMS were used to extract channel or watershed characteristics and to divide sub-basins. In addition, the initial and constant-rate method, user synthetic unit hydrograph method, and exponential recession method were used to estimate runoff volumes, the direct runoff hydrograph, and the baseflow hydrograph, respectively. The Muskingum model with variable parameters was then applied in the Louzigou Basin in Henan Province of China, and of the results, the percentages of flood events with a relative error of peak discharge less than 20% and runoff volume less than 10% are both 100%. They also show that the percentages of flood events with coefficients of determination greater than 0.8 are 83.33%, 91.67%, and 87.5%, respectively, for rectangular, triangular, and parabolic cross sections in 24 flood events. Therefore, this method is applicable to ungauged basins.
基金supported by the Scientific and Technological Basic Research Grant of the Ministry of Science and Technology of China (Grant No. 2007FY140900)the Public Welfare Industry Special Fund Project of the Ministry of Water Resources of China (Grant No. 200801033)
文摘The parameter X of the Muskingum method is a physical parameter that reflects the flood peak attenuation and hydrograph shape flattening of a diffusion wave in motion. In this paper, the historic process that hydrologists have undergone to find a physical explanation of this parameter is briefly discussed. Based on the fact that the Muskingum method is the second-order accuracy difference solution to the diffusion wave equation, its numerical stability condition is analyzed, and a conclusion is drawn： X ≤ 0.5 is the uniform condition satisfying the demands for its physical meaning and numerical stability. It is also pointed out that the methods that regard the sum of squares of differences between the calculated and observed discharges or stages as the objective function and the routing coefficients C0, C1 and C2 of the Muskingum method as the optimization parameters cannot guarantee the physical meaning of X.
文摘由于沅水水系五强溪水库流域面积大,流量控制站少,且洪水进入库区后,洪水波的传播方式变化较大,因此五强溪水库近坝区的洪水预报难度大。为提高五强溪库区洪水预报精度,采用XAJ-DCH模型(Xin′anjiang Digital Channel Model)对近坝区2016~2020年间13场洪水进行模拟,模型河道汇流分别采用了非线性水库法和马斯京根法,根据两种汇流方法的特点制定了两种不同的洪水预报方案。模拟结果表明:XAJ-DCH模型中两种河道演算方法均表现良好且简单实用,13场洪水的确定性系数基本位于0.7以上。非线性水库方法相比于马斯京根法考虑了河段断面情况以及水力特性,能够体现洪水运动的时空变化,且只需要率定河道糙率,其他参数如河道坡降、河宽以及河段长均可根据数字高程模型进行估计;马斯京根法需要率定4个河道参数,但马斯京根法模拟结果相比于非线性水库方法稍好。研究成果可为科学有效开展库区洪水预报、提高预报精度提供参考。
