Browsing by Author "Sreebhadra, M.N."

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Extreme response analysis for TLP-type floating wind turbine using Environmental Contour Method
    (CRC Press, 2022) Sreebhadra, M.N.; Rony, J.S.; Karmakar, D.; Guedes Soares, C.G.
    The reliability of structures against extreme loading conditions is a significant factor to be accounted for the design of marine structures. In Environmental Contour Method, using inverse reliability technique the most significant contributing environmental factors associated with the structure at the particular site can approximately give the long-term extreme response. In the present study, the extreme responses on five different configurations of TLP-type floating offshore wind turbine are analysed using the environmental contour method. The various responses including the maximum and minimum tower base bending moment loads at the blade root, tower base shear force is studied. The simulations are performed for the different wind speed and wave and a comparative study is made for the different TLP-type platforms. The estimation of extreme responses is obtained using the Environmental Contour Method and the present study will be helpful for the long-term load estimation of offshore structures. © 2022 the Author(s).
  • No Thumbnail Available
    Item
    Wave trapping due to composite pile-rock structure coupled with vertical barrier
    (SAGE Publications Ltd, 2023) Sreebhadra, M.N.; Krishna, K.R.A.; Karmakar, D.
    The wave transformation due to pile-rock porous structure in combination with vertical porous barrier is studied under oblique wave action. The pile-rock breakwaters consists of two rows of closely spaced piles and a rock core between them is effective in dissipating wave energy when compared with traditional rigid breakwaters due to its reduced deadweight of construction materials and additional stability. Three different cases of the vertical barrier configurations such as fully-extended barrier, bottom-standing barrier and surface-piercing barrier placed in front of the pile-rock porous structure are considered for the investigation. The numerical study is performed using the eigenfunction expansion and the associated orthogonal mode-coupling relations considering the continuity of pressure and velocity for the vertical barrier, seaward and leeward structural interfaces. The Darcy’s law is incorporated for the flow through porous media and the porosity factor of the structure is introduced using the complex porous effect parameter. The numerical results for the wave reflection, transmission and dissipation coefficient, wave force on front and rear side of porous structure along with the wave force on the barrier interface are evaluated for different hydraulic characteristics. The analysis is presented for varying structural porosity, angle of incidence, structural thickness, friction factor, length between vertical barrier and porous structure for the three different cconfigurations of vertical barrier. The numerical investigation performed in the present study will be useful for the design and analysis of the composite breakwater system to protect the offshore facility from high waves. © IMechE 2022.