Hydrodynamic measurements and modeling in the coastal regions of Northern Oman

Three-dimensional (3D) modeling of the coastal area of Muscat was done using Delft3D software to understand the hydrodynamic flow and current circulation pattern in the coastal region. The calibration and validation of the model were performed using the real-time values of water surface elevation and current. Excellent agreement with the observed water level (RMSE < 0.07 m; R > 0.99); and a good agreement with the current measurements (RMSE ≤ 0.2 m/s; R ≥ 0.7) was observed. The vertical turbulent eddy viscosity and diffusivity in the 3D model were computed using the turbulence closure model. The sensitivity of the three turbulence closure models (namely k-Ɛ, k-L, and algebraic model) was compared with the field data collected by an Acoustic Doppler Current Profiler (ADCP) deployed at three coastal locations near Muscat city. The results showed that the turbulence closure models used in the present study over-predicted the current approximately by 0.1 m/s during spring tide, and by 0.5 m/s in the neap tide events. The vertical profile analysis using the curve fitting demonstrated that the 1/5th power law best outlines the shape of ADCP and the 1/6th power law for the turbulent model, compared to the typical 1/7th power law. Further investigation is required to determine appropriate values of the parameters of turbulence closure models in order to achieve better accuracy in calculating near-bottom velocities.