Numerical Analysis of Local and Global Hydroelastic Response of Wetdeck Slamming Events on Multihull Vessels

Slamming;Hydroelastic;Wetdeck;Fluid-Structure Interaction;Catamaran;Naval Architecture and Marine Engineering;Engineering;Naval Architecture & Marine Engineering

Graham, MatthewYoung, Yin Lu ;

University of Michigan

关键词: Slamming;    Hydroelastic;    Wetdeck;    Fluid-Structure Interaction;    Catamaran;    Naval Architecture and Marine Engineering;    Engineering;    Naval Architecture & Marine Engineering;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/147495/grahmatt_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Catamarans operating in a large sea state encounter slamming events on the wetdeck that may lead to structural failure. Wetdeck slamming is a non-linear process which involves complex free-surface topology, high-velocity water jets, and breaking waves interacting with the bow and deck-hull geometry. The slamming process generates large pressures and loads that are time dependent and concentrated in space. The structure responds in a coupled manner to the complex fluid loading. Common approaches to design for the limiting slamming loads include analytical models or segmented model tests. Analytical slamming models assume a linear free-surface, prescribed velocities, and simplified geometries. These simplified assumptions make it difficult to apply to realistic cases. Experimental model tests capture slamming loads by using segmented models attached to a backspline. It is difficult to scale results to full-scale and to recreate model scale conditions that lead to the limiting load cases.A high-fidelity fluid-structure interaction solver is used to study a simplified impact problem and slamming on a catamaran. The canonical problem is a flat plate impacting a curved water surface. A detailed analysis is conducted on the simple flat plate showing the influence of boundary conditions, structural non-linearities, and the relative impact velocities. A new adaptive inertial under-relaxation scheme is developed for solving the artificial added mass instabilities due to the segregated coupling of the CFD and FEA models. Catamaran slamming simulations compare the influence of global loads on the local wetdeck structure. The full field data provided by the numerical solver is used visualization of flat wetdeck slamming loads. Careful evaluation of existing impact models are presented and recommendations for reduced order modeling of maximum stress during wetdeck slamming are provided.