Journal of Marine Science: Research & Development
Open Access

Abstract

Vellar estuary is one of the most prominent and best studied estuary of India in terms of its chemistry and biology, but less studied in terms of its hydrodynamics. In this study, a 2D closed grid high resolution bathymetry was developed using ODOM hydrotrac single beam echo-sounder. Wind, wave, tide and current parameters were measured in upper, middle and lower estuary of the Vellar estuary during southwest monsoon. The tidal signals were analyzed for major harmonic tidal constituents using MIKE-21. A 2D hydrodynamic model was developed with sophisticated software MIKE-21. The depth of the estuary ranged between 0.295 m and 18.235 m with an average of 4.435 m. The maximum wind speed was measured 10 knots and the predominant wave direction was SSW due to the south-westerly wind. The values of wave energy density varied between 0.18 and 1.41 J/m2 and it is relatively high, because the wave action was high during southwest monsoon. Form numbers calculated from the major tidal constituents conformed that the tidal pattern of the Vellar estuary is semi-diurnal. The current speed decreased from the upper estuary to lower estuary. Bottom friction in the Vellar estuary strongly affects the speed of the currents. Hydrodynamic model results show the evolution of the tidal currents over both the incoming and outgoing tides during spring and neap simulations. The hydrodynamic model calibration and validation illustrate the model is capable of accurately predict the hydrodynamics of the Vellar estuary.

Biography

Email: mugilarasan.ost@gmail.com