ABSTRACT It is desirable for naval architectures to simultaneously bear high force and dissipate dynamic energy. A structural protection approach via a specifically designed all-metal stiffened member with bistable components is proposed, which not only exhibits high stiffness but also an order of magnitude increase in the structural damping compared to that of a traditional member under wave impact

ABSTRACT The efficient management of marine vessels ensures that ships could operate smoothly and navigate at the most efficient level. Thus, the environmentally friendly voyage realises with the optimised running cost. Such a management approach could be achieved via a planned and proper maintenance strategy on the critical parts of the marine vessels’ combustion engines. Accordingly, in this study

ABSTRACT In this study, free vibration analysis of cracked plates was performed by using peridynamics (PD). A peridynamic Mindlin plate formulation was used and the numerical implementation was done using commercial finite element software, ANSYS. First, the formulation was verified by considering intact and cracked plates and peridynamic solutions were compared against numerical, theoretical and experimental

ABSTRACT A simple dynamic positioning (DP) system has been developed for the scaled model of a novel twin-lift decommissioning operation. Such a decommissioning solution involves the two semi-submerged vessels transporting the topside to another vessel. And it requires the synchronised motion of the two topside-carried vessels at a low speed, under the environmental disturbances. In order to ensure

ABSTRACT Design and fabrication procedures used in spherical pressure hull construction have been described in this paper. An appropriate design standard has been applied to ensure the safety and reliability of the pressure hull. Considering the material and manufacturing facility available, steel has been chosen as the pressure hull material. Design and manufacturing of spherical pressure hull have

ABSTRACT A commonly assumed ship-to-ship collision scenario is a rigid ship bow hitting the side of a ship perpendicularly. A bulbous bow has a slender shape overall but a rounded end, while a stem has a sharp horizontal edge but a gently sloping body. It was found from numerical simulations that the stem collision induces horizontal shear failure on side shell as soon as the stem contacts with the

ABSTRACT A CFD-based adjoint solver tool is presented to modify the hullform of a trimaran ship. Cost function of optimization process is considered total for resistance of trimaran at cruise speed. Mesh sensitivity gives sensitivity of the cost function associated with mesh deformation. Mesh morphing tool is implemented to alter the geometry without the need to revisit the CAD environment. The position

ABSTRACT Liquefied natural gas (LNG) exhibits significant environmental advantages. However, the hazards of LNG-fuelled ships need to be investigated in their early design stages, particularly with regard to accidental fuel leakage. In this study, a hypothetical oil tanker model was used with a fuel gas supply system installed on the main deck; the objective was to establish a critical zone for natural

ABSTRACT An experimental programme and nonlinear finite element analysis are carried out to examine the ultimate strength characteristics of stiffened panels with a crack and pits, under uni-axial longitudinal compressive loads. The test results are used to validate the finite element models. A series of nonlinear finite element analysis is performed with the validated models to illustrate the ultimate

ABSTRACT Pipeline installation into deep waters puts higher demands for the laying design. To reveal pipelay parametric effects on the pipeline dynamic behaviours, this study developed a dedicated finite element model (FEM) for deepwater S-lay system in light of OrcaFlex. This FEM sufficiently considered the clashing contacts between the pipeline and stinger rollers as well as pipe-seabed interactions

ABSTRACT Sideline is a key component of fish sensory system, which has been found to affect many behaviours of fish, including manoeuvring obstacle avoidance, prey tracking and environmental mapping in complex fluid environment. In this paper, based on the sensing flow field mechanism of fish lateral line system, a sphere obstacle model is established by using the CFD method and FLUENT software, and

ABSTRACT A numerical model was proposed to analyse the combined effect of the pneumatic breakwater and the submerged breakwater for improving the wave damping performance, in which the Reynolds Averaged Navier-Stokes equations combined with the Shear Stress Transport (SST) k-ω turbulence model were adopted to investigate the flow field. A series of existing experiments were applied to validate the

ABSTRACT The scattering of surface gravity waves by a skirt wall breakwater is analysed in two dimensions under the assumption of small-amplitude wave theory. The oscillatory wave past the porous skirt walls is assumed to follow Darcy’s law. The boundary value problem is solved using multi-domain boundary element method to obtain the numerical results for the different number of porous skirt walls

ABSTRACT Flexible risers are composite cylindrical structures, which are widely used in offshore oil and gas production facilities. Failure of a flexible riser during operation causes major economic and environmental losses. The improvement of structural integrity programs based on nondestructive techniques and risk-based inspections is therefore utterly important. In this article, the feasibility

ABSTRACT A numerical analysis and experimental validation of sloshing phenomenon in three-dimensional square tank with varying resonant frequency and amplitude of excitation is carried out in this study. Numerical simulations using fluid-structure interaction (FSI) was carried out and validated with experimental result. Square tank is numerically simulated with 50, 100 and 200 mm of water height excited

ABSTRACT A precise estimation of the welding deformation is an essential process in improving steel fabrication processes for building ships and offshore structures. This study validated the effect of the optimal simultaneous welding on the mitigation of welding displacements. Most previous studies on the optimised welding sequence for the reducing welding displacements have focused on one welding

Oceanographic research vessels (ORVs) are used to collect ocean data and analyse them to understand the physical, chemical and biological characteristics of seawater, seabed and other ocean-related factors affecting climate changes. These task require vessel to track a predefined trajectory at different speeds. It is crucial to understand the effect of different speed on manoeuvring characteristics

In this study, the genetic algorithm (GA) was implemented for the multi-objective optimization of the structural design of a pressure hull. The objective functions sought the maximum ultimate strength of the ring-stiffened cylindrical shell structure with minimum structural weight and maximum volume of the configured structural member. First, the evaluation models of several design variables of submarine

Energy efficient and environmentally friendly shipping have been primary concerns for the maritime industry. One of the alternatives to overcome these issues onboard is organic Rankine cycle (ORC) waste heat recovery system (WHRS). In this study, a transcritical ORC WHRS for a marine diesel engine is investigated at different engine operating loads by thermodynamic and environmental analysis. The engine

The problem of oblique water wave diffraction by three asymmetrically arranged vertical porous barriers with different widths in infinitely deep water is investigated. Reflection and transmission coefficients are evaluated, applying single-term Galerkin approximation. The amount of energy loss is derived employing Green's integral theorem. Wave force is determined using the linear Bernoulli equation

Marine structures are subjected to slamming loads characterised by high hydrodynamic pressure within short time durations. Such loads can cause local and global damages to structures. This paper, which is Part I in a series, reports a numerical investigation of slamming loads acting on flat stiffened plates and their dynamic response. The nonlinear explicit finite element code LS-Dyna with the Multi-Material

Dismasting is one of the most serious hazards for sailing boats. This event is mainly due to structural defects, poor maintenance or adverse weather conditions. For what the last aspect is concerned, it may be associated to two types of loads: the direct action of the wind on sails and accelerations caused by ship motions. The aim of this paper is to focus on the accelerations induced on the mast by

According to the shape and structure characteristics of ray in the ocean, a passive damping anti-rolling device was designed for fishing boats, platforms on the ocean, pontoon, heavy lift vessel and small ships that were used in maritime navigation or offshore operations. The dynamics model of the systems were established using three-dimensional (3D) computational fluid dynamics (CFD) software, the

Currently, most existing studies and specifications for container stack and securing system are corresponding to static conditions. In this paper, we attempt to investigate the dynamic effects caused by hull movement on the stack and securing system. Based on Froude scaling laws, the four-tier 20-ft ISO container stack and lashing equipment scaled models are constructed. The physical and structural

Marine transportation is fast witnessing an increased trend towards being all electric. This work puts forth offshore electric floating charging stations (FCS) as the need of the hour for pushing forward the transition from a completely fuel-based propulsion system to electric-powered vessel. Evaluation of a solar photovoltaic-based FCS for electric ships is made in this study and it puts forward novel

The system-level reliability analysis of DPS-3 Dynamic Positioning (DP) control system is proposed, which include both a qualitative failure modes and effects analysis (FMEA) and a quantitative analysis. The FMEA results show that the single point failure of main components of DP control system will not have any global effect on automatic positioning, however, the components involved with high Risk

This paper proposes a robust methodology for predicting extreme structural responses of offshore wind turbines. This robust methodology starts with forecasting an improved IFORM (Inverse-First-Order Reliability Method) environmental contour line through the use of principal component analysis. It then performs stochastic time domain simulations of an offshore wind turbine based on the information of

Serious environmental impacts of a ship's life cycle occur during building and end-of life phases. In this study, data gathered from the related sites in Turkey for steel hull building and its reverse process of steel hull recycling phases for different type of ships have been assessed by using SimaPro 8.2.3 software and CML-IA methodology to determine impact categories of abiotic depletions, acidification

This paper investigates wave-current-structure interaction considering both the following and opposing current. Experiments were conducted in a wave flume to determine wave transformation characteristics (i.e. wave reflection, transmission, and dissipation) employing both regular and irregular waves propagating in the presence of smooth and rough breakwaters. Discrepancies in the wave transformation

Shallow water studies of ship hydrodynamics typically examine a single, constant underwater canal cross-section at a time. In practice, the underwater cross-sectional area and shape of the waterway is rarely maintained constant over long distances. This study presents an attempt to quantify the effects of an abruptly varying water depth by numerically modelling such a condition using CFD. The results

The experimental and numerical investigations of the hydrodynamic response on 3-column and 4-column semi-submersible floaters with the same displacement, supporting a wind turbine in regular and random waves have been carried out in the present study. Experiments have been conducted in a laboratory wave flume using 1:75 scale models with the catenary mooring system. The numerical simulations have been

(2020). A Pioneer of Naval Architecture. Ships and Offshore Structures: Vol. 15, No. 5, pp. 453-453.

(2020). A Pioneer of Naval Architecture. Ships and Offshore Structures: Vol. 15, No. 5, pp. 454-454.

(2020). A Pioneer of Impact Engineering. Ships and Offshore Structures: Vol. 15, No. 5, pp. 455-461.

(2020). A Pioneer of Maritime Safety. Ships and Offshore Structures: Vol. 15, No. 5, pp. 462-467.

(2020). A Pioneer of Naval Ship Design. Ships and Offshore Structures: Vol. 15, No. 5, pp. 468-473.

This paper presents a Finite element modelling of the compression process of columns prepared by filling reinforced concrete (R.C.) in unplasticised polyvinyl chloride (UPVC) tubes and exposed to artificial seawater. Total 36 reinforced concrete-filled UPVC tubular (RCFUT) column specimens of length 800 mm are used for modelling. The UPVC tubes having 160, 200 and 225 mm diameters are used as a tube

A numerical method that coupled a Reynolds-averaged Navier-Stokes solver with a quasi-static and a dynamic mooring model was employed and compared. Decay tests of the freely floating and the moored buoy in calm water determined the system's linear and quadratic damping characteristics. In regular waves, predicted heave and pitch amplitudes and high-frequency surge amplitudes based on the quasi-static

The consequence of the near realistic modelling of collision damage shape on the post-accidental ultimate hull girder strength of double-hull oil tanker is investigated. For known striking ship’s geometry of the bulbous bow, damaged elements are removed from the finite element model of the midship section of the struck ship. Progressive finite element collapse analysis is then performed to determine

The aim of the paper was to develop a test database of the ultimate strength characteristics of full-scale steel stiffened plate structures under axial compressive loading at a temperature of −80°C. This paper is a sequel to the authors’ articles (Paik et al. 2020a PaikJK, LeeDH, NohSH, ParkDK, RingsbergJW. 2020a. Full-scale collapse testing of a steel stiffened plate structure under cyclic compressive

In order to mitigate dynamic responses of floating offshore wind turbines (FOWTs) under combined wind-wave-current loading, employment of structural control techniques is often considered. In this paper, a novel concept of a passive FOWT structure is proposed to overcome the previous limitations on space and mass of tuned mass dampers (TMDs). The conceptual design is examined on the basis of a finite

Although it is well known that the slamming-induced whipping can significantly increase the structural loading of ships, its consequence on the hull girder's collapse is still unclear. Moreover, the whipping-induced stresses are having a higher frequency than the wave-induced stresses. Hence some doubts are cast on the probability that the dynamic effects may provide additional strength reserves. This

In this study, the hydrodynamic performance of a partially submerged vertical slotted barrier was investigated on the basis of an analytical and numerical approach in regular waves. The matched eigenfunction expansion method (MEEM) was used to solve the boundary value problem including the porous boundary condition. Herein the drag coefficient representing the energy dissipation was estimated by the

Reducing the ship’s drag is an effective technique for reducing emissions, operating expenses, and improving EEDI. For slow-moving vessels, frictional resistance has been reported to contribute up to 80% of total resistance, demanding a thorough investigation in reducing it. Air or the gas has been used as a lubricant, to reduce the frictional resistance known as Micro Bubble Drag Reduction, which

The aim of this work is to simulate the complex 3D hydrodynamics inside free-surface anti-roll tanks with obstacles and side sub-compartments. The case studies comprise a rectangular tank, a tank with a C-shaped section and a rectangular tank with baffles, for which experimental results are provided. The simulations have been performed for 3 and 6 degrees of roll, and for various filling levels. The

Numerical simulations are performed to study the interaction between propeller and hull for two planing vessels: a hard-chine and a tunnelled craft. The numerical model used for reproduction of the problem is validated by comparing the obtained results against published data, showing that a morphing technique is more reliable compared to an overset one. It is demonstrated that propellers strongly affect

The PMMA frustums applied as observation windows in the deep-sea manned cabins are vital substructures.The accurate measurement and calculation of the real displacement of PMMA frustums are important for designing the space between the window and the metal pressure hull. The total displacement during service of the submersible is time-dependent due to the viscoelastic properties of PMMA material. In

The present study focus on the wave-structure interaction of a caisson type offshore intake well with the regular waves. A 1:20 scale model is experimentally investigated with and without curtain wall in the shallow wave basin for its hydrodynamic responses like wave run-up, rundown, and free surface water oscillation inside the well. The wave run-up and rundown on all the faces record maximum when

Recently, safety protection research on the risk of flammable gas leakage and deflagration between adjacent offshore facilities is easy to be ignored and the fire and explosion accidents are also harmful to interactive operations, causing great injury to personnel and damage to structures. In this paper, safety analysis of a flammable gas leakage and deflagration disaster is carried out on an FPSO

The work deals with an experimental and numerical assessment of crack growth in a welded stiffened panel subjected to a cyclic load of a sine shape. A stiffened panel with one central stiffener is manufactured for testing cracks simultaneously propagating in the plate and web. The unified fatigue growth rate equation proposed by Cui et al. 2011 CuiWC, WangF, HuangXP. 2011. A unified fatigue life prediction

The paper presents the conversion of an oil tanker into FPSO to be operated in Gulf of Mexico (GoM) considering the strength and fatigue analyses. First, hydrodynamic analysis is performed for a typical full load condition and a typical ballast condition in order to determine hydrodynamic loads for ultimate strength and fatigue for operating as an FPSO in GoM. The section scantlings are then generated

A modified incremental-iterative method for bulk carriers under alternate hold loading condition is outlined, focusing on the assessment of the local stress field, due to double bottom bending by the orthotropic plate theory, and the development of a modified strain field of double bottom structures, after first failure of bottom stiffeners occurs. Particularly, the ISSC bulk carrier is assumed as

A numerical model based on multi-domain boundary element method (BEM) is developed to study the gravity wave interaction with a horizontally submerged wavy porous plate. The boundary condition on the porous barrier is considered a quadratic pressure drop to incorporate the effect of wave height on the wave energy dissipation directly. The performance characteristics of the wavy porous plate are studied

The structural integrity of platform components under operational loads and environmental storm conditions is required for risk assessment and inspection plan development. In-place analysis was performed to verify that the platform structural members have the robustness and capability to support the loads in operating and storm conditions. A finite-element analysis is adopted to estimate the in-place

Many wave energy converter (WEC) designs emerging over the recent years are floating cylindrical geometries with position-keeping mooring system. However, the dynamic stability of these novel floating structures under random sea states has not been investigated adequately. The Melnikov function model and the Markov process model are two efficient approaches providing quantitative predictions of capsizing

The current blast wall design guidelines do not capture the random nature of underlying parameters. The main issues are the appropriate treatment of various uncertainties in the explosion loadings and the complex blast wall behaviour considering dynamic and nonlinearity effects. To capture these effects a new methodology needs to be developed based on probabilistic reliability assessment. To address

Hydrodynamic performance plays an important role on energy consuming and safety for autonomous underwater vehicles (AUVs). The hydrodynamics of the whole process of AUV free running pushed by a rotating propeller was investigated with physics-based simulations by using multi-block hybrid dynamic grids method, URANS, coupled to 6DOF and UDFs. The AUV had cruised for approximately 14.1 s and 7.105 m

Increasing competition in the international shipbuilding industry pushes the naval architect’s pressure to reduce the costs of design and manufacturing of new buildings. Using newly developed Additive Manufacturing (AM) methods in the framework of industry 4.0 revolution can offer new opportunities in the manufacturing of labour-intensive and complex parts. Wire Arc Additive Manufacturing (WAAM) is

This paper is a sequel to the authors’ earlier article Paik et al. [2020a. Full-scale collapse testing of a steel stiffened plate structure under cyclic axial-compressive loading, Structures, https://doi.org/10.1016/j.istruc.2020.05.026]. The aim of the paper was to present a test data on the ultimate compressive strength characteristics of a full-scale steel stiffened plate structure at cryogenic

Hawser single point moored (SPM) shuttle tankers are widely used in various offshore oil development system. In this paper, the experiment of 1:40 shuttle tanker model with hawser SPM system in irregular waves is carried out. The effects of loading status, wave parameters, hawser line length and stiffness on the motion response of the shuttle tanker are investigated, including the amplitude, frequency