Behavior of a Pontoon Supported by a Mooring Dolphin in a Tsunami (First Report)

2013 ◽  
Vol 135 (2) ◽  
Author(s):  
Mitsuhiro Masuda ◽  
Koichi Masuda ◽  
Tomoki Ikoma ◽  
Kuniaki Shoji
Keyword(s):  
Tsunami Wave ◽  
Container Terminal ◽  
Three Dimensional ◽  
Simulation System ◽  
Floating Body ◽  
Disaster Prevention ◽  
Floating Structure ◽  
Marine Disaster ◽  
Moving Particle ◽  
Present Simulation

In recent years, a number of floating facilities for the utilization of ocean space, such as a marine disaster prevention base, floating restaurant, or floating container terminal, are planned, and some of them are actually built. Most of these facilities are of the pontoon-type floating structure, and the mooring system is basically a mooring dolphin. In the design of such facilities, it is important that the prediction of the motions of a pontoon-type floating body, supported by a mooring dolphin, in a tsunami is obtained. The objective of the present research is to develop a simulation system to obtain such predictions. In the present simulation system developed here, the three-dimensional (3D) MPS method (moving particle semi-implicit method) is used, and a solitary wave and borelike wave are applied to represent the incoming tsunami wave. The present paper is a report of the first stage of the research, and the heaving motion of the floating body acted upon by the tsunami is paid special attention, and we also report on the results of the study of the detaching of the floating body from the mooring dolphin.

Behavior of the Pontoon Supported by Mooring Dolphin in Tsunami

2011 ◽  
Author(s):  
Mitsuhiro Masuda ◽  
Koichi Masuda ◽  
Tomoki Ikoma ◽  
Kuniaki Shouji
Keyword(s):  
Solitary Wave ◽  
Simulation System ◽  
Container Terminals ◽  
Floating Body ◽  
Mooring System ◽  
Disaster Prevention ◽  
Floating Structure ◽  
Marine Disaster ◽  
Floating Type ◽  
Present Simulation

In recent years, the floating facilities for the ocean space utilization such as the marine disaster prevention base, the floating restaurant, floating type container terminals are planned and some of those facilities are actually built. Most of these facilities are the pontoon type floating structure, and the mooring system is a mooring dolphin. In the design of such facilities, it is important that the prediction of the behavior of the pontoon type floating body supported by mooring dolphin in tsunami the objective of present research is to develop the simulation system for the prediction of the behavior of the pontoon type floating body supported by mooring dolphin in tsunami. In present simulation system, the 3D-MPS method is applied, and the solitary wave and the bore like wave are applied as a assumed tsunami. The present paper is a report of the first stage of the research, and the heaving motion on floating body in the tsunami is paid to attention, and it reports on the result of examining the detaching from mooring dolphin of floating body.

scholarly journals The Numerical Modeling of Coupled Motions of a Moored Floating Body in Waves

Water ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1748 ◽  
Author(s):  
Lin Cheng ◽  
Pengzhi Lin
Keyword(s):  
Numerical Model ◽  
Water Waves ◽  
Three Dimensional ◽  
Numerical Results ◽  
Floating Body ◽  
Mooring Line ◽  
Floating Structure ◽  
Structure Interaction ◽  
Coupling Procedure ◽  
Boundary Force

Nonlinear interactions between water waves and a moored floating body are investigated using the virtual boundary force (VBF) method. The paper first introduces an in-house three-dimensional viscous incompressible flow model (NEWTANK), which is used to simulate wave-floating structure interaction by using the VBF method. Then the coupling procedure between the mooring line model and the floater model is described. Some validation cases of the developed model, including the motions of a free-floating box in two different water waves, are presented. The present numerical results will be compared with the available experimental data and other numerical results from the published literature. After that, the validity of the mooring line in the numerical model is simulated by simulating the motions of a floating box in still water. Finally, the verified model is applied to analyze the wave-induced motions of a catenary moored floating structure, investigating the motion responses and mooring forces responses. The numerical results agree well with the experimental measurements on the whole. This indicates that the present numerical model can correctly capture the main features of the wave-moored floating structure interaction.

A Research on Characteristics of Responses of a Floating Structure in Tsunami

2004 ◽  
Author(s):  
Koichi Masuda ◽  
Tomoki Ikoma ◽  
Maki Uchida ◽  
Akira Takeda
Keyword(s):  
Wave Theory ◽  
Floating Body ◽  
Present System ◽  
Convolution Integral ◽  
Floating Bodies ◽  
Floating Structure ◽  
Exciting Forces ◽  
Mooring Forces ◽  
Analysis System ◽  
Present Simulation

The objective of present paper are to establish the practical numerical analysis system for responses of motions and mooring forces on a floating structure induced by Tsunami and to clarify the characteristics of responses on floating bodies in tsunami. In the present analysis system, the initial tsunami profile is evaluated by Mansinha-Smylie’s Method and propagating tsunami profiles are calculated by linear long wave theory and also the tsunami exciting forces on floating body are computed by the numerical wave tank based on VOF method [5] and then the motions and mooring tether forces due to Tsunami on floating body are predicted by the convolution integral method. The usefulness of present system is confirmed by comparing with the experimental results on Tsunami exciting forces on floating bodies. The responses of floating body due to tsunami using fault models of Tokai and Tonankai earthquakes are computed by using the present simulation system so that the characteristics of responses on floating bodies are examined and are clarified.

Container port throughput analysis and active management using control theory

2021 ◽  
pp. 147509022110208
Author(s):  
Cuong Truong Ngoc ◽  
Xiao Xu ◽  
Hwan-Seong Kim ◽  
Duy Anh Nguyen ◽  
Sam-Sang You
Keyword(s):  
Control Theory ◽  
Time Series Data ◽  
Sliding Mode ◽  
Container Terminal ◽  
Three Dimensional ◽  
Maritime Transportation ◽  
Container Terminals ◽  
Active Management ◽  
Dynamical Analysis ◽  
Series Data

This paper deals with three-dimensional (3D) model of competitive Lotka-Volterra equation to investigate nonlinear dynamics and control strategy of container terminal throughput and capacity. Dynamical behaviors are intensely explored by using eigenvalue evaluation, bifurcation analysis, and time-series data. The dynamical analysis is to show the stability with bifurcation of the competition and collaboration of multiple container terminals in the maritime transportation. Based on the chaotic analysis, the sliding mode control theory has been utilized for optimization of port operations under disruptions. Extensive numerical simulations have been conducted to validate the efficacy and reliability of the presented control algorithms. Particularly, the closed-loop system has been assessed through chaotic suppression and synchronization strategies for port management. Finally, the presented fundamental techniques can be utilized to provide managerial insights and solutions on efficient seaport operations that allow more timely and cost-effective decision making for port authorities in such a highly competitive environment.

Optimization of the Navy’s three-dimensional mine impact burial prediction simulation model, Impact35, using high-order numerical methods

2021 ◽  
pp. 154851292110286
Author(s):  
Athanasios Donas ◽  
Ioannis Famelis ◽  
Peter C Chu ◽  
George Galanis
Keyword(s):  
Numerical Analysis ◽  
Numerical Methods ◽  
Prediction Model ◽  
Simulation Model ◽  
Three Dimensional ◽  
Simulation System ◽  
High Order ◽  
Alternative Methodology ◽  
Runge Kutta ◽  
Fifth Order

The aim of this paper is to present an application of high-order numerical analysis methods to a simulation system that models the movement of a cylindrical-shaped object (mine, projectile, etc.) in a marine environment and in general in fluids with important applications in Naval operations. More specifically, an alternative methodology is proposed for the dynamics of the Navy’s three-dimensional mine impact burial prediction model, Impact35/vortex, based on the Dormand–Prince Runge–Kutta fifth-order and the singly diagonally implicit Runge–Kutta fifth-order methods. The main aim is to improve the time efficiency of the system, while keeping the deviation levels of the final results, derived from the standard and the proposed methodology, low.

A Numerically Efficient Method for Analysis of Very Large Articulated Floating Structures

1998 ◽  
Vol 42 (03) ◽  
pp. 174-186
Author(s):  
C. J. Garrison
Keyword(s):  
Hydrodynamic Interaction ◽  
Near Field ◽  
Three Dimensional ◽  
Computational Effort ◽  
Floating Structure ◽  
Complete Structure ◽  
Field Interaction ◽  
Floating Structures ◽  
Computing Effort ◽  
The Individual

A method is presented for evaluation of the motion of long structures composed of interconnected barges, or modules, of arbitrary shape. Such structures are being proposed in the construction of offshore airports or other large offshore floating structures. It is known that the evaluation of the motion of jointed or otherwise interconnected modules which make up a long floating structure may be evaluated by three dimensional radiation/diffraction analysis. However, the computing effort increases rapidly as the complexity of the geometric shape of the individual modules and the total number of modules increases. This paper describes an approximate method which drastically reduces the computational effort without major effects on accuracy. The method relies on accounting for hydrodynamic interaction effects between only adjacent modules within the structure rather than between all of the modules since the near-field interaction is by far the more important. This approximation reduces the computational effort to that of solving the two-module problem regardless of the total number of modules in the complete structure.

Numerical Research on FPSOs With Green Water Occurrence

2009 ◽  
Vol 53 (01) ◽  
pp. 7-18
Author(s):  
Renchuan Zhu ◽  
Guoping Miao ◽  
Zhaowei Lin
Keyword(s):  
Three Dimensional ◽  
Green Water ◽  
Floating Body ◽  
Incoming Wave ◽  
Model Case ◽  
Floating Structures ◽  
Design And Optimization ◽  
Head Waves ◽  
Wave Heights ◽  
The Impact

Green water loads on sailing ships or floating structures occur when an incoming wave significantly exceeds freeboard and water runs onto the deck. In this paper, numerical programs developed based on the platform of the commercial software Fluent were used to numerically model green water occurrence on floating structures exposed to waves. The phenomena of the fixed floating production, storage, and offloading unit (FPSO) model and oscillating vessels in head waves have been simulated and analyzed. For the oscillating floating body case, a combination idea is presented in which the motions of the FPSO are calculated by the potential theory in advance and computional fluid dynamics (CFD) tools are used to investigate the details of green water. A technique of dynamic mesh is introduced in a numerical wave tank to simulate the green water occurrence on the oscillating vessels in waves. Numerical results agree well with the corresponding experimental results regarding the wave heights on deck and green water impact loads; the two-dimensional fixed FPSO model case conducted by Greco (2001), and the three-dimensional oscillating vessel cases by Buchner (2002), respectively. The research presented here indicates that the present numerical scheme and method can be used to actually simulate the phenomenon of green water on deck, and to predict and analyze the impact forces on floating structures due to green water. This can be of great significance in further guiding ship design and optimization, especially in the strength design of ship bows.

Sign in / Sign up

Export Citation Format

Share Document