Faculty Publications
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Item Performance evaluation of submerged breakwater using Multi-Domain Boundary Element Method(Elsevier Ltd, 2021) Patil, S.B.; Karmakar, D.The gravity wave interaction with submerged breakwater of different structural configurations are investigated based on the small-amplitude wave theory. The boundary value problem is analysed in two-dimension using the linearized wave theory in water of finite depth. The submerged breakwater structural configuration such as (i) thin-walled type (impermeable), (ii) rectangular type (impermeable and permeable), (iii) triangular type (impermeable, permeable, perforated), (iv) trapezoidal type (impermeable, permeable, perforated) and (v) Tandem type (impermeable, permeable, perforated) are considered to analyse and performance of the breakwater. The numerical model is developed using the Multi-Domain Boundary Element Method (MDBEM) to analyse the hydrodynamic scattering coefficient (such as reflection, transmission and dissipation coefficient) for the change of physical parameters such as relative spacing between the breakwaters, relative water depth and structural dimensions. The convergence of the present numerical model is performed for the specific case of tandem breakwater and numerical computation is validated with the results available in the literature. The wave reflection and transmission coefficient along with wave force on the structure is analysed for different shapes, structural parameters and geometrical parameters of the breakwater to maximize the efficiency of breakwater. In the case of permeable breakwater, the submerged tandem breakwater is found to be more efficient in wave transformation as compared to rectangular, triangular and trapezoidal permeable submerged breakwaters. The comparative analysis performed on different configurations of the breakwater in the present study will be helpful in the effective design of the breakwater near the harbour regions. © 2021 Elsevier LtdItem Hydrodynamic analysis of an H-shaped pile-restrained floating breakwater combined with a pair of vertical barriers(Elsevier Ltd, 2024) Panda, A.; Karmakar, D.; Rao, M.The present study analyses the performance of a composite breakwater consisting of an H-shaped breakwater attached with vertical/inclined barriers held from both sides using the Multi-Domain Boundary Element Method (MDBEM). The study is performed to analyse the wave transformation characteristics (reflection and transmission), wave energy dissipation and horizontal wave forces due to the gravity wave-structure interaction. The hydrodynamic performance of the integrated breakwater is performed due to the effect of changing various structural properties such as porosity, width and depth of structural elements, relative spacing between breakwater and barrier, angle of incidence and the inclination of the barriers. The boundary conditions and the corresponding edge conditions are incorporated for each surface and interface and correlated with Green's function to solve the boundary value problem. The detailed study proposes the suitable dimensions of the structural elements of the breakwater for optimal performance. The application of inclined barriers over the vertical barrier in certain conditions for maximising wave reflection is presented and analysed to understand the effectiveness of the barrier inclination. The favourable barrier dimensions and the suitable relative spacing for deep water regions are discussed, and the effect of rigidity and porosity of the barriers are analysed to maximise breakwater performance in wave attenuation. On considering the suitable design parameters and structural stability, the composition of vertical/inclined barriers with an H-shaped pile-restrained floating breakwater serves as a protective component by encountering maximum wave force and dissipating considerable wave energy to provide an efficient solution in harbour protection. © 2024 Elsevier LtdItem Hydrodynamic performance of H-shaped floating breakwater in the presence of a partially reflecting seawall(Taylor and Francis Ltd., 2025) Panda, A.; Muduli, R.; Karmakar, D.; Rao, M.The present study examines the hydrodynamic interaction of surface gravity waves with freely floating H-shaped porous structure situated close to a partially reflecting seawall and without seawall using Multi-Domain Boundary Element Method (MDBEM). The study is performed to examine the performance of the H-shaped floating breakwater for sway, heave, and roll motion, as well as the effects of a seawall on the hydrodynamic parameters associated with the floating body. The horizontal wave force, added mass, radiation damping coefficients, and the horizontal, vertical, and moment acting on the floating structure are analysed under different structural configurations. The numerical model developed using MDBEM approach is validated using the results available in the literature. The primary findings demonstrate that reducing the structural moments and added mass and wave force coefficients, and constructing a seawall adjacent to the breakwater, greatly enhances performance in deep water. The reflection coefficient by the seawall greatly impact damping in shallow water depth but have minimal effect in deep water region, indicating that water depth significantly impacts the wave transformation. The present study provides important insights for developing marine infrastructure in various coastal and offshore environments by demonstrating the potential for customised engineering solutions to reduce wave impacts successfully. © 2025 Informa UK Limited, trading as Taylor & Francis Group.Item Effect of seabed condition on the hydrodynamic performance of a pile-restrained H-shaped floating breakwater(Taylor and Francis Ltd., 2025) Panda, A.; Karmakar, D.; Rao, M.The present study investigates the hydrodynamic analysis of pile-restrained H-shaped porous breakwater for various seabed conditions using the small amplitude wave theory. The Multi-Domain Boundary Element Method (MDBEM) is employed to investigate the influence of parametric variations on the hydrodynamic coefficients and horizontal wave force under normal and oblique incident waves. The numerical accuracy is ensured by comparing it with the available literature. The numerical investigation on the hydrodynamic performance of the H-shaped breakwater is performed for various seabed configurations considering different angles of slope, the width of slope/step/obstacle, step height, number of steps, soil permeability, angle of wave incidence, the width of flange and submergence draft of the web of the H-shaped structure. The findings indicate that the seabed undulation has a higher wave impact on the breakwater than the horizontal seabed. In addition, the study suggests that the sloped seabed is preferable in deeper water depths to reflect waves efficiently and the seabed permeability can affect the hydrodynamic coefficients in shallow and intermediate water depths. The study performed on the H-shaped breakwater for varying seabed topography will be helpful in the design and construction of a suitable H-shaped breakwater for an effective wave absorber in coastal regions. © 2025 Informa UK Limited, trading as Taylor & Francis Group.Item Hydroelastic analysis of VLFS integrated with multiple porous vertical barriers(Taylor and Francis Ltd., 2025) Hemanth, S.; Karmakar, D.The hydroelastic response of Very Large Floating Structures (VLFS) integrated with multiple porous vertical barriers of finite width is analyzed using small amplitude wave theory. The integrated system consists of a floating VLFS and porous barriers of finite-thickness designed to mitigate wave-induced structural effects. A coupled Multi-Domain Boundary Element Method (MDBEM) and Finite Difference Method (FDM) is employed, with MDBEM considered to model the fluid domain and barriers of finite thickness, while FDM is used to numerically model the VLFS. Numerical validation performed in the study confirms the accuracy of the results with the existing literature. The findings indicate that porous barriers effectively absorb wave impact, thereby reducing the forces exerted on the VLFS and minimizing the hydroelastic response, which enhances structural integrity and safety. The study also examines the influence of hydroelastic responses due to variation in barrier porosity, orientation, and placement of porous barriers. The study provides valuable insights which will be significant for optimizing VLFS design and improving resilience in maritime environments. © 2025 Informa UK Limited, trading as Taylor & Francis Group.Item Hydroelastic analysis of VLFS integrated with porous floating box breakwater using multi-domain boundary element method(Elsevier Ltd, 2025) Hemanth, S.; Karmakar, D.The present study analyses the feasibility of integrating a Very Large Floating Structure (VLFS) with a porous floating box-type breakwater kept fixed in its position to analyze the hydroelastic responses within the integrated system based on linearized wave theory. The integrated VLFS-breakwater system, comprising the VLFS and the porous box-type breakwater assures in mitigating the structural effects induced by waves. The coupled Multi-Domain Boundary Element Method (MDBEM) and Finite Difference Method (FDM) are employed to investigate the performance of integrated VLFS-breakwater system. The computational framework employs the MDBEM to model the fluid domain and the floating breakwaters, while the VLFS is modeled using the FDM approach. The study considers three distinct relative positions of the VLFS integrated with a floating breakwater on (i) the leeside, (ii) the seaside, and (iii) on both leeside and seaside of the VLFS. The numerical study is performed based on thin-plate theory and small amplitude wave theory. The study corroborates its numerical findings with existing literature, supporting the validity of its methodology. The integrated system effectively reduces forces acting on the VLFS by absorbing the primary impact of waves. Consequently, the hydroelastic response of the VLFS is reduced, preserving its structural integrity and enhancing overall safety. The study signifies the importance of integrating the porous box-type breakwater with the VLFS. The importance of the orientation of the structure towards the sea waves, the porosity of the breakwater, the effect of relative spacing between the breakwater and VLFS and variations in hydrodynamic responses with respect to the placement of the floating breakwater are thoroughly discussed. The study performed will be helpful in the design and implementation of integrated VLFS-breakwater system, enhancing their robustness and safety in maritime environments. © 2024 Elsevier LtdItem Influence of seabed topography on hydroelastic behavior of VLFS integrated with porous breakwater(Elsevier Ltd, 2025) Hemanth, S.; Karmakar, D.The present study investigates the effect of seabed topography on the hydroelastic behaviour of a Very Large Floating Structure (VLFS) integrated with porous floating breakwaters for inclined, irregular, stepped and irregular stepped seabed conditions. The real-world marine environments feature complex topographies that significantly influence wave-structure interactions. The integrated system combines a flexible VLFS with porous floating breakwaters designed to attenuate wave energy and mitigate structural responses. A coupled Multi-Domain Boundary Element Method (MDBEM) for fluid dynamics and the Finite Difference Method (FDM) for structural analysis is employed for the computation, allowing for accurate modelling of wave-structure-seabed interactions. The numerical model developed for the MDBEM-FDM approach is validated against established benchmark results available in the literature. The key parameters, such as seabed slope, seabed irregularity, breakwater porosity, and placement, are analysed to evaluate their impact on hydrodynamic forces, bending moments, and strain distributions. The numerical results indicate that irregular seabed can amplify localized bending stresses by up to 30 % compared to flat beds, while inclined seabed alters wave reflection patterns, intensifying asymmetric loads. However, porous breakwaters effectively reduce transmitted wave energy by 40–50 %, suppressing adverse hydroelastic responses. The study emphasizes the importance of considering seabed topography while designing VLFSs integrated breakwater. The presence of the breakwater helps in the reduction of the stresses brought on by uneven seabed conditions by strategically placing them and optimizing their porosity. The findings from the present study can contribute to the development of resilient VLFS systems in real-world marine environments, ensuring structural integrity under varying seabed conditions. © 2025 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.