Design of a Minor Fishing Harbor in India with Special Reference to Training of the Mouth of River Chapora

Abstract: This paper treats the derivation of a two-dimensional differential equation, which describes the phenomenon of combined refraction - diffraction for simple harmonic waves, and a method of solving this equation The equation is derived with the aid of a small parameter development, and the method of solution is based on the finite element technique, together with a source distribution method

Abstract: Kraus, N.C. and Harikai, S., 1983. Numerical model of the shoreline change at Oarai Beach. Coastal Eng., 7: 1–28. A numerical simulation was made of the long-term shoreline evolution of the sandy beach adjacent to Oarai Harbor, Japan. The sand transport and shoreline change at Oarai are dominated by wave diffraction at a long breakwater and interruption of the current and sand transport at a large groin. The model was first calibrated using detailed wave data for a recent 7 1 2-month period. The shoreline change which occurred over three years was then simulated to verify the model's predictive capability. The calculation procedure for the breaking wave height and angle along the beach under combined diffraction and refraction was also verified with field measurements. The availability of detailed wave and survey data stimulated a number of improvements in the calculation procedures for the breaking waves and shoreline change. A comprehensive description of the site is given, and relevant shoreline survey and wave data are listed in an appendix to enable interested parties to test and refine their own models.

Abstract: The coastline of Kannyakumari (8°4′N 77°33′E to 8°13′N 77°14′E), along the Arabian Sea is located near the southern tip of the Indian peninsula. This coast experiences heavy erosion particularly during the seasonal monsoons. This in turn results in considerable damage to properties, economic loss and leads to a number of socio economic problems. Protection measures in the form of groins have been implemented at selected locations along the coast. Prediction of shoreline oscillation due to the presence of such structures is extremely important prior to their construction. Although several formulae are available in the literature for the prediction of long shore sediment transport, studies regarding their application and validation with field problems along this coast are scanty. In the present work, seasonal measurements of shoreline oscillation adjacent to the shore connected structures were carried out during the year 2007 for which satellite data have also been adopted. These measurements are adopted to validate a finite difference based numerical model based on the formulation of Janardanan and Sundar (1994) for the prediction of shoreline evolution in the presence of shore connected structures. The offshore wave climate for the year 2007 is simulated from National Centre for Environmental Prediction (NCEP) wind data using Wave Analysis Model (WAM) model, whereas, the near shore wave climate was derived by adopting MIKE21 Parabolic Mild Slope (PMS) module The alongshore sediment transport is calculated using the approach of Van Rijn (2001) . The prediction revealed that the net average annual alongshore transport varies from about 0.008 to 0.040 million m3 and is towards the west.

Abstract: The dynamics of micro-tidal inlets is quite complicated as their stability is controlled both by the littoral drift and the tidal range. Thus the process of assessing their stability is not well understood and quite challenging. This paper brings out the process of assessing the stability aspects of inlets using numerical codes. The equilibrium between the longshore transport rate and spring tidal prism ensures the stability of inlet between ocean and estuary. However, any disturbance to this equilibrium leads to the closure of the inlets. The active movement of sediments in the surf zone are due to the long shore velocity, the driving force for the littoral drift, which is obtained with the application of time domain model, FUNWAVE, a public domain software. With the driving force thus obtained, the long shore transport is then estimated through empirical relations from which, the stability of the inlet is assessed. The spring tidal prism is the discharge of the flow entering into the ocean from inlets/estuaries. The flow velocity is determined by the application of shallow water model. The input data for the nearshore circulation due to waves and currents are mostly measured from the field. For the current study, the Kondurpalem inlet(14001′07″N, 80009′24″E)along the East coast of Indian peninsula is investigated and its seasonal variation is assessed. The stability state of the inlet is re-assessed by providing necessary training works. The stability of the trained inlet is found to be more stable and the minimum depth and width to be maintained in the inlet gorge can be established through this process.