Análisis de postproceso caso de modelización propia del estudio: calibration of manning's roughness in non-instrumented rural basins using a distributed hydrological model

Abstract

The objective of the case study "Calibration of Manning's roughness in non-instrumented rural basins using a distributed hydrological model" is to be able to approximate a Manning coefficient with vegetation and grassland covers in non-instrumented basins. For this, a comparison of hydrograms of the basins selected in the Iber and HEC-HMS program will be made, in which the hydrogram to be calibrated will be those obtained in the Iber software, it is highlighted that the variation of this coefficient allows more precise calculations of speed, discharge and depth of water in each discretization cell of the basin, which represents a more accurate output hydrograph with reality.

For the case study, three basins with vegetation cover were taken, for the value of numerical curves the use of the land, the topographic characteristics of the area and the hydrological condition of the basin were taken into account, assuming a CN value of 70 and a precipitation of 75mm.

According to the results, in the three basins a positive correlation was obtained between the Manning coefficients and the total precipitation values, the best correlation being that of basin two, because in this the Manning coefficient increases with the same intensity as the precipitation values, demonstrating that although the HEC-HMS software is not sensitive to changes in the coefficient, whether they influence precipitation data.