Modelling of flow in the Khoshk ephemeral river, Shiraz

Most of investigator has applied Saint-Venant equations to simulate unsteady flow in the river systems. However, these equations have no terms to consider infiltration along the river. They need some modifications to be able to simulate flow in the seasonal rivers such as Khosk River, Shiraz (Iran). Due to non infiltration terms in the unsteady flow equations, most of existing software is not able to simulate flow in the ephemeral river. In the present study, efforts have been made to apply a mathematical model to be able to simulate flow through ephemeral rivers. Due to existence of an option in the HD parameter section of MIKE 11 software, it has been selected for simulation process of the selected case study. As a case study, field data of Khoshk River have been collected from the local water authorities’ database. Several scenarios have been assumed for simulation process and their corresponding data have been entered in the software database. The most important factor in the ephemeral river is Manning’s roughness coefficient and the transmission loss coefficient. As a result, Manning’s roughness coefficient and the transmission loss for different branches of the river system have been estimated using calibration concept. Developed model has been validated successfully. Finally, developed model has been employed to simulate flow hydrograph and its important characteristics such as peak flow, time to peak and base time. It is shown that MIKE 11 is able to simulate ephemeral river flow characteristics in the ephemeral river, successfully

کلیدواژه ها:

Simulation ، Ephemeral ، Transmission loss ، MIKE11 ، Khoshk River