Faculty Publications
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Item Wave transformation due to floating elastic thick plate over changing bottom topography(Springer, 2019) Praveen, K.M.; Karmakar, D.In the present study, the wave interaction with floating thick elastic plate is studied over changing bottom topography. The effect of flexible floating plates is studied based on Timoshenko–Mindlin’s theory in finite water depth and shallow water approximations. The hydroelastic analysis is performed at varying water depths and plate sizes to get the behaviour of elastic plate under the action of ocean wave. Different bottom topography cases are considered in the analysis of wave interaction with floating thick elastic plate. A mathematical model considering the mode-coupling relation along with the orthogonality condition is formulated to analyse the wave scattering due to floating thick elastic plate with varying bottom topography. The numerical results for the hydroelastic behaviour are obtained for wave interaction with floating plate with free-edge condition in varying bottom topography. The present analysis helps to understand the significance of rotary inertia and transverse shear deformation for the floating elastic plates. The study provides an insight into the effect of seabed profile over the wave interaction with floating thick elastic plate in finite water depth. © Springer Nature Singapore Pte Ltd. 2019.Item Hydroelastic analysis of articulated floating elastic plate based on Timoshenko–Mindlin plate theory(Taylor and Francis Ltd. michael.wagreich@univie.ac.at, 2018) Praveen, P.; Karmakar, D.; Guedes Soares, C.G.The wave interaction with articulated floating elastic plate is investigated considering the Timoshenko–Mindlin thick plate theory for both finite and shallow water depths. The elastic plates are modelled as finite flexible floating structure interconnected with vertical linear/rotational spring stiffness. The eigenfunction expansion method along with the orthogonal mode-coupling relation is used to analyse the hydrodynamic behaviour of the interconnected structure. The study is performed for different articulated edge conditions for varying plate thickness and water depths to understand the behaviour of articulation under the action of an ocean wave. The hydroelastic response of the interconnected floating elastic plate with different connector stiffness is observed to compare well with the result available in the literature. The present study provides an insight into the effect of articulated joints with varying spring stiffness for the suitable design of the structure. © 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group.Item Wave Interaction With Floating Elastic Plate Based on the Timoshenko-Mindlin Plate Theory(American Society of Mechanical Engineers (ASME) infocentral@asme.org, 2019) Praveen, K.M.; Karmakar, D.; Guedes Soares, C.In the present study, the wave interaction with the very large floating structures (VLFSs) is analyzed considering the small amplitude wave theory. The VLFS is modeled as a 2D floating elastic plate with infinite width based on Timoshenko-Mindlin plate theory. The eigenfunction expansion method along with mode-coupling relation is used to analyze the hydroelastic behavior of VLFSs in finite water depth. The contour plots for the plate covered dispersion relation are presented to illustrate the complexity in the roots of the dispersion relation. The wave scattering behavior in the form of reflection and transmission coefficients are studied in detail. The hydroelastic performance of the elastic plate interacting with the ocean wave is analyzed for deflection, strain, bending moment, and shear force along the elastic plate. Further, the study is extended for shallow water approximation, and the results are compared for both Timoshenko-Mindlin plate theory and Kirchhoff's plate theory. The significance and importance of rotary inertia and shear deformation in analyzing the hydroelastic characteristics of VLFSs are presented. The study will be helpful for scientists and engineers in the design and analysis of the VLFSs. © 2019 by ASME.Item Hydroelastic analysis of a truss pontoon mobile offshore base(Techno Press technop2@chollian.net, 2019) Sakthivel, S.; Panneer Selvam, R.; Karmakar, D.Very Large Floating Structures (VLFS) are one among the solution to pursue an environmentally friendly and sustainable technology in birthing land from the sea. VLFS are extra-large in size and mostly extra-long in span. VLFS may be classified into two broad categories, namely the pontoon type and semi-submersible type. The pontoon-type VLFS is a flat box structure floating on the sea surface and suitable in regions with lower sea state. The semi-submersible VLFS has a deck raised above the sea level and supported by columns which are connected to submerged pontoons and are subjected to less wave forces. These structures are very flexible compared to other kinds of offshore structures, and its elastic deformations are more important than their rigid body motions. This paper presents hydroelastic analysis carried out on an innovative VLFS called truss pontoon Mobile Offshore Base (MOB) platform concept proposed by Srinivasan and Sundaravadivelu (2013). The truss pontoon MOB is modelled and hydroelastic analysis is carried out using HYDRAN-XR*for regular 0°waves heading angle. Results are presented for variation of added mass and damping coefficients, diffraction and wave excitation forces, RAOs for translational, rotation and deformational modes and vertical displacement at salient sections with respect to wave periods. © 2019 Techno-Press, Ltd.Item Hydroelastic analysis of periodic arrays of multiple articulated floating elastic plate(Taylor and Francis Ltd. michael.wagreich@univie.ac.at, 2020) Praveen, K.M.; Karmakar, D.; Guedes Soares, C.The periodic array of multiple articulated floating elastic plate acted upon by ocean waves is analysed considering Timoshenko-Mindlin plate theory. The floating elastic plate is placed periodically and is interconnected with vertical linear and flexural rotational springs which acts as an articulated joint. The hydroelastic behaviour of multiple articulated floating elastic plate is analysed based on eigenfunction expansion method along with the orthogonal mode-coupling relation in finite water depth and the continuity of energy and mass flux are used in the hydroelastic analysis of floating plate at shallow water depth. Further, the application of the wide-spacing approximation (WSA) method is employed to analyse the hydroelastic characteristics of the multiple articulated floating elastic plate. The results obtained using the eigenfunction expansion method is compared with the results based on WSA at finite water depth and validated with the results available in the literature. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group.Item Hydroelastic response of floating elastic plate in the presence of vertical porous barriers(Taylor and Francis Ltd., 2022) Praveen, K.M.; Venkateswarlu, V.; Karmakar, D.The attenuation of the incident wave interacting with a very large floating structure (VLFS) in the presence of vertical barriers is analysed considering small amplitude wave theory. The VLFS is considered to be articulated and is modelled based on Timoshenko-Mindlin plate theory. The eigenfunction expansion method along with the orthogonal mode-coupling relation is employed for the case of finite water depth. The numerical study is performed to analyse the wave reflection, transmission and dissipation characteristics due to the articulated floating plate for the case of bottom standing and surface piercing vertical porous barriers. The hydroelastic behaviour in terms of deflection and strain for an articulated floating thick elastic plate in the presence of porous barriers is analysed. The study reveals that the magnitude of wave attenuation is enhanced due to the presence of vertical porous barriers and also provides an understanding in mitigating the structural response. © 2020 Informa UK Limited, trading as Taylor & Francis Group.Item Wave transformation due to finite floating elastic plate with abrupt change in bottom topography(Taylor and Francis Ltd., 2022) Praveen, K.M.; Venkateswarlu, V.; Karmakar, D.The propagation of surface gravity waves in the presence of finite floating elastic plate over varying sea bottom profile is investigated using the Timoshenko-Mindlin plate theory. The continuity of velocity and pressure at the interfaces along with the continuity of deflection, slope, bending moment and shear force is employed with the support conditions at the plate edges. The numerical computation is performed to obtain the hydroelastic behaviour of the floating elastic plate due to abrupt change in bottom topography. The validation of the present analytical model is performed with the known results available in the literatures. Further, a detailed comparison of the numerical results is presented for different step bottom topography on the hydroelastic characteristics of a floating elastic platform. The present study will provide an insight into the effect of the ocean bottom profile on wave propagation due to the presence of a large floating elastic plate. © 2021 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 Hydrodynamic analysis of floating VLFS using multi-domain boundary element method(Springer Nature, 2025) Hemanth, S.; Karmakar, D.The present study emphasizes the investigation of rigid and flexible Very Large Floating Structures (VLFS) by analyzing the reflection and transmission coefficients, plate deflections and wave force on the floating structure. The study involves analyzing the hydrodynamic characteristics of a porous and rigid VLFS, and hydroelastic analysis of flexible VLFS. The analysis is performed using the coupled Multi-Domain Boundary Element Method (MDBEM) and Finite Difference Method (FDM) at finite water depth. The flexible VLFS is modelled based on the Euler–Bernoulli thin plate theory and the study is performed using small amplitude wave theory. The study evaluates the hydroelastic behaviour in terms of structural deflection and hydrodynamic parameters by varying the structural porosity. The reflection and transmission coefficients are analyzed to show the extent of wave propagation on the lee side and the seaside of the structure. The wave force coefficients obtained signify the importance of the structure's orientation for the oncoming waves. The numerical results are validated with the results available in the literature. The analysis is performed for different structural and material properties to obtain the minimal hydroelastic and hydrodynamic response to assess the optimum design criteria and suitability of the type of VLFS, thereby maintaining the stability of the structure for safer operations. © The Author(s) 2025.Item 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.