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Item Nondimensional methods to classify the tidal inlets along the Karnataka coastline, west coast of India(Springer, 2019) Amaranatha Reddy, N.; Mendi, V.; Seelam, J.K.; Rao, S.This classification of tidal inlets is essential to maintain the stability of the inlets as well as to study the changing patterns of tidal inlets in India. Tidal inlets around the world have been classified as either wave-dominated or tide-dominated or river-dominated, since the 1970s. Tidal inlet classification for 471 inlets along the coast of India was carried out by Vikas M et al., based on wave and tide information. But only 30 inlets were considered for river-based classification due to lack of discharge information. In order to consider the river-based classification, the river flood discharge was estimated using Synthetic Unit Hydrograph (SUH) methods for Karnataka coast. In this study, 29 tidal inlets along the coast of Karnataka are selected for the classification based on river discharge. The classification has been done in two aspects; without considering wave period (Formula Presented) where Qtide is peak tidal discharge, Qf is river discharge and H is wave height. The results obtained are validated with hydrological and geomorphological classifications and the dominant forces over the dynamics of the inlets are determined. © Springer Nature Singapore Pte Ltd. 2019.Item Tidal energy estimation of potential tidal inlets along the east coast of India(Springer, 2019) Mendi, V.; Amaranatha Reddy, N.; Seelam, J.K.; Rao, S.The power consumption is increasing with modernization of infrastructure and with the depleting fossil fuels. The need to look for alternate sources of energy generation has already reached a peak. The production of power from renewable energy sources is considered to be on a large scale in the near future because of the abundant sources across the country. One of the most reliable sources is the tidal energy as it can be extracted both by kinetic and potential means at the tidal inlets. The process of extracting tidal potential energy by storing the water during the high tide and release during low water is a well-established method. However, there are many parameters that are to be considered for the potential energy extraction. Two such important parameters, i.e. tidal range and basin area are considered in this study. The interrelationship between these two parameters and its overall influence on potential tidal energy estimation is studied. Along the four coastal states, excluding the Gulfs, around 250 tidal inlets have been identified (Vikas, M.Tech. thesis, 2015 [8]). Considering the standards of existing tidal power plants, tidal energy sites for energy extraction are estimated and will be presented in this paper. © Springer Nature Singapore Pte Ltd. 2019.Item Classification of tidal inlets along the central west coast of India(Elsevier Ltd, 2015) Mendi, M.; Reddy, N.A.; Rao, S.; Seelam, J.K.Tidal inlets along the Maharashtra coast on the central west coast of India were classified according to three methods available in the literature. Two classification methods viz., (i) Hydrodynamic classification (Hayes, 1979) and (ii) Classification based on dimensionless parameters (Vu, 2013) used for the classification are compared with the morphological classification of de Vriend et al., (1999). The hydrodynamic classification of Tidal inlets along Maharashtra coast is carried out considering mean annual significant wave height. The classification is also extended considering significant wave heights obtained for South-West monsoon, North-East monsoon and Fair Weather seasons. It has been observed that 74% of the inlets are tide dominated as per morphological classification whereas considering annual mean wave heights in Vu (2013) method, 67% of the inlets are wave dominated. © 2015 The Authors. Published by Elsevier Ltd.Item Classification of tidal inlets along the central east coast of India(Elsevier Ltd, 2015) Reddy, N.A.; Mendi, M.; Rao, S.; Seelam, J.K.Coastal inlets are the openings along the coastline that provide a linkage between the open ocean and the hinterland water bodies. These coastal inlets are varied in nature depending on many influencing parameters such as tide, wind, river flow and waves. Amongst these parameters, the tides are the most regular while waves and freshwater flow are more seasonal. The tidal inlets have to be examined and studied to understand the nearshore coastal processes. The inlet remains stable (i.e. open) as long as the alongshore sediment bypasses the tidal inlet. Classification of coastal systems in a broader view is necessary for the management of tidal inlets. There are several methods to classify tidal inlets based on different perspectives namely geo-morphological, hydrodynamic etc. In the present study, tidal inlet classification is carried out considering the hydrodynamics and morphodynamics along the Andhra Pradesh coast, considering the classification method as in Hayes (1984) and Thuy (2013). The Hayes (1984) classification considers only the tidal range and significant wave height, whereas Thuy (2013) considers discharge due to tide (∼Tidal prism/tide duration) and wave (∼√gH5). A total of 108 tidal inlets along Andhra Pradesh coast on the east coast of India are classified considering annual mean wave height (Hs) as well as seasonal wave heights. This paper presents the methods used and results of the coastal classification along the central east coast of India. © 2015 Published by Elsevier Ltd.Item Urbanization Challenges in Emerging Economies(American Society of Civil Engineers (ASCE) onlinejls@asce.org, 2017) Mendi, V.; Reddy, N.A.; Lokeshwari, M.; Raghavendra, T.; Seelam, J.K.Tidal inlet is an opening along the coast which facilitates the exchange of water and nutrients. The energy extracted at the tidal inlet using tides is called tidal energy. Tidal energy is reliable and not depleting. Since the density of seawater is 800 times denser than air, the energy extraction is much favorable and reliable resource. Because of the above said advantages, tidal energy production has become an important energy source at global platform. The study area chosen is the Sri Lankan coast. The tidal condition along the Sri Lankan coast is semi diurnal. Identification of the locations for energy extraction is important as the width of the identified inlet at the coast plays an important role in energy extraction. Also, parameters like tidal range, basin area have to be taken into account in order to consider the inlet suitable for energy extraction. In this paper, tidal inlets will be identified along the Sri Lankan coast, the data will be collected for the parameters that are required to consider an inlet for energy extraction and the potential energy that can be extracted at the inlets will be assessed. © 2018 American Society of Civil Engineers.Item Estimation of potential tidal energy along the West Coast of India(World Scientific, 2018) Mendi, V.; Seelam, J.K.; Rao, S.Tidal energy is one of the clean and non-depleting renewable energy sources. In contrast to other clean sources, such as wind, solar, geothermal etc., tidal energy can be predicted for years ahead. Also, the medium, seawater, is more than 800 times denser than air and the astronomic nature of the underlying driving mechanism results in an essentially predictable resource, although subject to weather-related fluctuations. These features make it an important energy source for global power production in the near future. There are various types of tidal power plants across the world with varying tidal elevation. Also the method of conversion of the tidal energy into electrical energy is site specific. For example, we can adopt conventional method to extract energy in high tidal regions. But when it comes to low tidal regions like the southern India where tidal elevation measurements does not exceed 2.5m, there is a need of low flow turbines which can extract higher energy from lower head. An important factor that is responsible for the velocity of tidal stream is the tidal inlet dimensions. In this paper, an attempt has been made to identify the feasible locations for extraction of potential tidal energy along the Indian Coast. © 2018 World Scientific Publishing Co. Pte. Ltd.Item Flood estimation at ungauged catchments of western catchments of Karnataka, West coast of India(Taylor and Francis Ltd. michael.wagreich@univie.ac.at, 2019) Amaranatha Reddy, N.A.; Seelam, J.K.; Rao, S.; Nagaraj, M.K.Many catchments in India are devoid of gauging stations. In the absence of measurements of stream flow, regional rainfall-runoff relationships developed over a hydro-meteorologically similar region may be used to estimate flood discharge at ungauged catchments. This study includes testing of different methods wherein a representative basin could be used to develop a Synthetic Unit Hydrograph (SUH) within its hydro-meteorological similar region. Derivation of SUH using Central Water Commission (CWC) flood estimation was tested on 13 catchments for Konkan and Malabar coasts on the west coast of India. The five methods are (i) CWC Dimensionless approach, (ii) Snyder method, (iii) SCS method, (iv) Two Parameter Gamma Distribution method and (v) Hybrid model. Inter-comparison of the SUHs and unit hydrographs derived from precipitation data is carried out. Amongst all methods tested the Two parameter Gamma Distribution method and Hybrid model satisfies the Unit Hydrograph criterion whereas, traditional methods of Snyder, SCS, CWC-SUH and CWC dimensionless methods require manual adjustments of the characteristics points and have a significant degree of subjectivity and trial and error. The above-said methods including CWC method are used to estimate flood discharge at ungauged catchments of the coastal districts along Karnataka coastline. © 2018, © 2018 Indian Society for Hydraulics.Item Surfzone currents at candolim and Miramar beaches of Goa, India: Measurements and comparisons(National Institute of Science Communication and Policy Research, 2014) Yadhunath, E.M.; Seelam, J.K.; Jishad, M.; Gowthaman, R.; C, C.; Pednekar, P.S.Measurements in the surfzone current are often carried out using Acoustic Doppler Velocimeters, Electromagnetic current meters, as well as visual observations based on floats. A simple approach is used to install an Aanderaa current meter in water depths less than a meter and the surfzone currents are measured for a period of about 2 hours during a rising tide. Surfzone wave heights and tide were also simultaneously measured and used to compute wave induced currents based on appropriate equations. The obtained current velocity compared with measured RCM data. Measurements were carried out separately at two beaches (Candolim and Miramar) which have varying topography and different surfzone conditions. © 2014, National Institute of Science Communication and Information Resources (NISCAIR). All rights reserved.Item Surfzone Wave Characteristics during Flood Tide on the Central West Coast of India(World Scientific Publishing Co. Pte Ltd michael.wagreich@univie.ac.at, 2015) Seelam, J.K.; Jishad, M.; Yadhunath, E.M.; C, C.; Gowthaman, R.; Pednekar, P.S.; Luis, R.; Mehra, P.Surfzone wave characteristics, measured using a wave and tide gauge (WTG) during a flood tide, were studied at three different beaches having different nearshore slopes. The spectral wave characteristics viz., wave-height and mean wave period were estimated considering different sample sizes. Inter-comparisons of wave climate between each of three beaches for a similar tide level are presented. The wave-height and mean wave period values obtained from the wave analysis for each of the record using waves by wave method show that surfzone wave-height increased with time during a flood tide and the mean wave period decreased with time up to mid tide and then increased during the rest of the measurement period at Keri and Miramar beaches. At Candolim, the reversing trend of mean wave period increase is observed to occur much before reaching the mid tide level. The surfzone waves during a flood tide indicated that the wave-heights increased with time while the mean wave period showed a decreasing trend in general. The variation of breaker index showed a decreasing trend from low tide to high tide ranging between 0.45 and 0.23. The surf similarity parameter estimated corroborates with the visual observations. © 2015 World Scientific Publishing Company.Item Evaluation of tidal stream energy at major tidal inlets of Goa, India(Taylor and Francis Ltd., 2022) Mendi, V.; Seelam, J.K.; Rao, S.An attempt has been made to identify promising sites for tidal stream energy assessment along the Goa coast on central west coast of India. A two-dimensional tidal-driven validated numerical model is used to assess the tidal stream velocities. The numerical model results are further used to estimate the tidal stream energy over the simulation period which would form a resourceful input for future to optimize locations of tidal energy farms. The locations of current maxima in each of the tidal driven regions have been identified and the energy is estimated thereof. This paper describes the tidal driven currents using a numerical model and their validation with measurements; and estimation of tidal stream energy among the different selected locations to choose the most feasible location for tidal energy extraction along Goa coast. © 2019 Indian Society for Hydraulics.