COMPARISON BETWEEN TWO NUMERICAL MODELS FOR PREDICATION OF HYDRAULICS AND MORPHOLOGICAL CHANGES IN THE RIVER NILE (KM 633 - KM 645 UPSTREAM El-RODA GAUGE STATION)

Abstract

The numerical models have effective and necessary tools for rivers hydrological and morphological studies. Numerical models are useful when results are required on scales applicable for hydrological and morphological changes, where velocity and water depth distributions are significant especially in river reaches. In the present study, two well-known hydraulic models are used to simulate the River Nile hydraulics and morphological changes. A sensitivity analysis is carried out for the two models to investigate the features and disadvantages of each model and give recommendations for their further applications. The performance analysis depends on field survey data and simulations. The two models are the SMS modules (FESWMS) model and the (Delft3D) model. The field data were collected for a study reach of 12 km which is located between km 633 to km 645, measured from El-Roda gauge station. The data included geometric and hydraulic data, that were gathered for calibration and validation of the models. The results indicated that both the SMS module and (Delft3D) model predicted the water surface elevations quite well. The sensitivity analysis showed that (Delft3D) model was more logical to mesh resolution than the SMS module and SMS model presented a better fit for the hydraulic variables. However, Delft3D presented a better fit for velocity and morphological changes.