Hydraulic models for the generation of flood inundation maps are not commonly applied in mountain river basins because of the difficulty in modeling the hydraulic behavior and the complex topography. This paper presen...Hydraulic models for the generation of flood inundation maps are not commonly applied in mountain river basins because of the difficulty in modeling the hydraulic behavior and the complex topography. This paper presents a comparative analysis of the performance of four twodimensional hydraulic models (HEC-RAS 2D, Iber 2D, Flood Modeller 2D, and PCSWMM 2D) with respect to the generation of flood inundation maps. The study area covers a 5-km reach of the Santa B-arbara River located in the Ecuadorian Andes, at 2330 masl, in Gualaceo. The model's performance was evaluated based on the water surface elevation and flood extent, in terms of the mean absolute difference and measure of fit. The analysis revealed that, for a given case, Iber 2D has the best performance in simulating the water level and inundation for flood events with 20- and 50-year return periods, respectively, followed by Flood Modeller 2D, HEC-RAS 2D, and PCSWMM 2D in terms of their performance. Grid resolution, the way in which hydraulic structures are mimicked, the model code, and the default value of the parameters are considered the main sources of prediction uncertainty.展开更多
水流在克服阻力过程中的能量转化是大比降山区河流水温变化的重要影响因素。以雅鲁藏布江大河湾河段为研究对象,采用数学模型方法,探讨了落差引起的摩擦内能在沿程水体温升中的贡献程度。研究结果表明:(1)雅鲁藏布江大河湾河段"派...水流在克服阻力过程中的能量转化是大比降山区河流水温变化的重要影响因素。以雅鲁藏布江大河湾河段为研究对象,采用数学模型方法,探讨了落差引起的摩擦内能在沿程水体温升中的贡献程度。研究结果表明:(1)雅鲁藏布江大河湾河段"派镇-解放桥"沿程250 km, 6~11月干流沿程实测水温变化明显,其温升幅度范围达到1.0~4.3℃,各月估算干流增温率范围为1.9~2.1℃/100 km,干流水体增温的热源较为稳定;(2)通过计入落差转换内能的河道纵向一维水温数学模型率定得到转化系数为0.7,模型能较好地反演研究河段的水温变化过程;(3)摩擦内能和水气热交换,是大河湾河段水体温升的主要因素,其中落差引起的水温升高幅度为3.7℃,对温升的贡献达到90%。研究成果可为大比降山区河流的水温研究提供理论与数据参考。展开更多
基金supported by the Research Directorate of the University of Cuenca(DIUC)
文摘Hydraulic models for the generation of flood inundation maps are not commonly applied in mountain river basins because of the difficulty in modeling the hydraulic behavior and the complex topography. This paper presents a comparative analysis of the performance of four twodimensional hydraulic models (HEC-RAS 2D, Iber 2D, Flood Modeller 2D, and PCSWMM 2D) with respect to the generation of flood inundation maps. The study area covers a 5-km reach of the Santa B-arbara River located in the Ecuadorian Andes, at 2330 masl, in Gualaceo. The model's performance was evaluated based on the water surface elevation and flood extent, in terms of the mean absolute difference and measure of fit. The analysis revealed that, for a given case, Iber 2D has the best performance in simulating the water level and inundation for flood events with 20- and 50-year return periods, respectively, followed by Flood Modeller 2D, HEC-RAS 2D, and PCSWMM 2D in terms of their performance. Grid resolution, the way in which hydraulic structures are mimicked, the model code, and the default value of the parameters are considered the main sources of prediction uncertainty.
文摘水流在克服阻力过程中的能量转化是大比降山区河流水温变化的重要影响因素。以雅鲁藏布江大河湾河段为研究对象,采用数学模型方法,探讨了落差引起的摩擦内能在沿程水体温升中的贡献程度。研究结果表明:(1)雅鲁藏布江大河湾河段"派镇-解放桥"沿程250 km, 6~11月干流沿程实测水温变化明显,其温升幅度范围达到1.0~4.3℃,各月估算干流增温率范围为1.9~2.1℃/100 km,干流水体增温的热源较为稳定;(2)通过计入落差转换内能的河道纵向一维水温数学模型率定得到转化系数为0.7,模型能较好地反演研究河段的水温变化过程;(3)摩擦内能和水气热交换,是大河湾河段水体温升的主要因素,其中落差引起的水温升高幅度为3.7℃,对温升的贡献达到90%。研究成果可为大比降山区河流的水温研究提供理论与数据参考。
