ABSTRACT This paper examines the hydroelastic problems of a two-dimensional symmetric flexible wedge water entry through free-fall motion. Water entry is numerically investigated by coupled Finite Volume Method and Finite Element Method using a strong two-way coupling approach. The emphasis of this study is on numerical approach and the paper provides an accurate two-way FSI coupling method for the

ABSTRACT In today’s marine industry, high-density polyethylene (HDPE) material has gained popularity due to its recyclability that relieves the concerns for sustainability of the products and its lightweight, resistance to environmental effects, such as moisture, corrosion, organisms, UV, etc. its sufficient mechanical properties. HDPE material may be combined with other light materials for structural

ABSTRACT The hydrodynamic behaviours and progressive collapse phenomenon of the submerged floating tunnel (SFT) under anchor cable breakage are experimentally investigated in this study. A physical scale segment model of the SFT under wave and current loadings is designed and studied in wave-current flume. A specially designed anchor cable breakage device is presented. The experimental data are observed

ABSTRACT The analysis of stresses imposed on structures by offshore environments is critical for their safety and smooth operation. Physical model testing for structural responses on offshore platforms is time-consuming and expensive. Computational fluid dynamics (CFD) can be used to predict hydrodynamic loads induced by fluid flow around an offshore platform. In CFD, model validation and verification

ABSTRACT Using Euler-Lagrange analysis the state-space model of the slosh-container system is obtained. This state-space description undergoes approximate linearization with the use of Taylor series expansion and the computation of Jacobian matrices around a temporary operating point which is recomputed at each iteration of the control method. For the approximately linearized model, an H-infinity feedback

ABSTRACT A yacht is a complicated product, and the design of the yacht involves highly complex procedures and activities because of its recursive cycle. Designing a reliable and a resilient yacht is an inherently tough issue. Therefore, it would be useful to develop novel methodologies for detecting, managing and mitigating potential risks at the design phase. This paper presents an approach to manage

ABSTRACT Liquefied Natural Gas (LNG) spills may cause steel to embrittle, leading to the brittle fracture of marine structures due to the cryogenic temperatures. For the integrity assessment of marine steel structures in the event of an LNG spill, first and foremost, an accurate heat transfer analysis is required. This study presents an experimental set-up that allows for thermal-structural analysis

ABSTRACT This paper presented theoretical and experimental models for the investigation of the amplitude of the vertical motion of a cylinder by a two-dimensional linear wave, passing through a circular horizontal cylinder close to the free surface in water. To consider the effect of the free surface, the Gap ratio = d/a was introduced by dividing the distance d between the centre of the cylinder and

ABSTRACT 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

ABSTRACT In this paper, three curved floating bridge concepts with a uniform span of 500 m and different radii of curvature are proposed for the crossing of the coastal waters in Singapore. The bridge girder is supported by 4 pontoons along the bridge length and the two ends are connected to the shore. Three different girder cross-sections are considered. Static analysis is first carried out considering

ABSTRACT The integrated bubbly wake strength of two ship models with different scales is investigated in this paper. The laser spot video recording technique is implemented to measure the light scattering properties of laser beams transmitted through the wake. The bubbly wake is generated by the movement of two geometrically similar models towed at constant velocities in a towing tank. The effect of

ABSTRACT Shipyards face tough problems such as ineffective production control and poor planning. Identifying appropriate work packages is one of the challenges of ship production planning. Work packages consist of a group of sub-works. The activities of block production that must be completed at each work station are referred to as sub-works. This study proposes a two-stage hierarchical model for assessing

ABSTRACT Condition-based maintenance is a maintenance strategy that implements Industrial Internet of Things to monitor the assets’ condition. Despite its undeniable benefits, several challenges are encountered, such as the incompleteness of sensor data. Hence, while data imputation is an important practise, there is a lack of analysis and formalisation of data imputation in the maritime industry.

ABSTRACT The fixed type foundation to support wind turbine in shallow water and floaters for medium to deep water depth, has been proposed in the literature. Among the floaters, semi-submersible floater has been shown promising with improved hydrodynamic response. In this study, the feasibility of semi-submersible type floater to support a vertical axis wind turbine (VAWT) has been investigated and

ABSTRACT Slender systems in which the length dominates over the other dimensions are an integral part of offshore systems. Modelling of such systems takes into account bending, sometimes torsional, and more rarely longitudinal deformations. The paper presents a new formulation of the segment method, in which the elongation of a slender link is considered; it is also possible to restrict analysis to

ABSTRACT This paper investigates the synchronization control problem for a supply vessel during underway replenishment with unknown dynamics, unknown disturbances, input saturation and unavailable velocities. A virtual trajectory shifted by a distance at an angle relative to the trajectory of the supplied vessel is planned. A high-gain observer observer is employed to estimate unavailable vessel velocities

ABSTRACT Breaking waves interaction with two tandem cylinders are numerically studied using Computational Fluid Dynamic (CFD) software OpenFOAM. The effects of transverse inclined angles of the downstream cylinder and separation distances between two cylinders on breaking wave loads and free surface elevations are investigated. The interface between air and water phases is captured by the Volume of

ABSTRACT The application of transient three-dimensional numerical code ITU-WAVE is presented for the prediction of hydrodynamic characteristics of floating bodies. The time histories of unsteady motions are directly presented with respect to Impulse Response Functions (IRFs). First-order steady forces of wave-resistance, sinkage force and trim moment are solved as the steady-state limit of surge radiation

ABSTRACT Emergency Rescue and Response Vessels (ERRV) is an integral component of any offshore emergency evacuation programme intended to recover and rescue personnel who have escaped or evacuated a facility from an accident event. This paper used Fuzzy Analytical Hierarchy Process (FAHP) and Evidential Reasoning (ER) methodology to assess the ERRV safety in offshore emergency response operations.

ABSTRACT Anti-shock design of shipboard equipment is an important part to ensure warship vitality. In this paper, based on the multi-body system discrete-time transfer matrix method, shock response calculation model of a diesel generator set is established, and the generation method of system overall transfer matrix based on the topological structure is established. Parameter study of anti-shock of

ABSTRACT An offshore structure is operated in an ocean wave environment that is stochastic in nature. Essential knowledge of ocean wave mechanics is practically important when it comes to the reliability of the structure. This paper summarised the numerical formulation involved in representing the ocean wave which will provide interaction effect in the design load of offshore structural response. Mechanism

ABSTRACT Fatigue-induced cracks of tubular joints are common in aged offshore structures which can be strengthened using grouted clamp connections. However, only limited guidance is available for design of these clamps. Hence, a comprehensive experimental and numerical investigation on the behavior and capacity of the grouted clamped joints has been carried out. In order to obtain the deformation and

ABSTRACT Mould bed is the most important equipment to control the deformation in the process of block construction. However, its height needs to be controlled separately based on the known height, and it affects the construction precision of block severely. Therefore, a dynamic union control method is proposed in this paper. Firstly, in order to realize the union control of mould bed system, the distribution

ABSTRACT Concrete semi-submersible floating wind turbines (FWTs) have generated increasing interest in the offshore wind energy industry due to their superiority over steel structures in aspects of construction and maintenance. However, the influence of construction materials on the dynamics of FWTs was scarcely studied before. The dynamics of two FWTs, mounted on a concrete and a steel Y-shaped semi-submersible

ABSTRACT An adaptable algorithm is proposed in this study, which can predict the complete load-shortening curve of a stiffened panel subjected to uniaxial longitudinal compression. The algorithm provides an extension to existing empirical formulae initially derived for predicting the ultimate compressive strength of stiffened panels. Based on observations from a series of nonlinear finite element analyses

ABSTRACT This study provides a detailed philosophical view and evaluation of a viable design for a large liquid hydrogen tanker fuelled by liquid hydrogen. Established methods for determining tank sizing, ship stability, and ship characteristics were used to evaluate the preliminary design and performance of the liquefied hydrogen tanker named ‘JAMILA’, designed specifically to transport liquid hydrogen

ABSTRACT This article presents a methodology for the reduction of ship structure vibration through local structural stiffness modifications. To identify the locations in the ship structure where the modifications should be made, three design criteria are considered: structural intensity, von Mises stress, and displacement. Two simple cases of cantilever beam and simplified ship were first tested under

ABSTRACT Modern optimisation methodologies have revolutionised the engineering sector and pave the way for innovation. In ship design, this has been spearheaded by the introduction of the Holistic Design approach that allows more attributes and performances of the end product to be assessed accurately and concurrently even at the early design phase. In this respect, the authors present herein a methodology

ABSTRACT Because the flow direction of the water above and below the interface of internal wave is opposite, internal wave has a strong shear effect on ocean structures. A dynamic model of internal wave acting on deep water steel catenary riser (DSRC) is built. The global dynamic responses of gas riser and oil riser under the same action of internal wave are both obtained through numerical calculation

ABSTRACT This paper presents a new simplified numerical approach (SNA) for predicting hydrodynamic data of underwater wings (UWs). Instead of full three-dimensional (3D) flow field analyses, SNA combines Vortex Lattice Method (VLM) and several two-dimensional Reynolds-Average Navier-Stokes (2D RANS) simulations of wing sections to gain results. Hence, SNA shows a remarkably lower computational cost

ABSTRACT The current research deals with the possibility of relying on wind energy, specifically Flettner rotors; as a source of ships propulsion to reduce ships’ emissions. The paper highlights the technical, environmental, and economic aspects of wind-assisted propulsion systems. As a case study, four Flettner turbines are examined to be used onboard a bulk carrier ship, considering three different

ABSTRACT Buckling is a crucial phenomenon to be considered in offshore pipelines and is dependent on the resistance of the surrounding soil, which depends on the diameter of the pipe (D) and embedment depth (H). In this study, the behaviour of the failure mechanisms and the capacity factors are investigated for a practical range of embedment depth (H) and diameter of offshore pipelines (D), using Indian

ABSTRACT SOLAS2020 damage stability regulations are based on probabilistic damage distributions. Those originate from the pooled analysis of collision accidents across a fleet with bias towards cargo ships. This paper introduces a method that accounts for collision-based crashworthiness on ship damage distributions. The method reshapes statistical SOLAS damage distributions for a given ship or structural

ABSTRACT An experiment was conducted on D36 steel plates under various corrosion scenarios. This was realised to determine the interactive effect of multiple corrosion pits on the compressive behaviour of stiffened plates and to establish a generalised design-oriented uniaxial material model for application in fibre element models to assess the strength and stability of ship structures. The performance

ABSTRACT Accurate prediction about the penetration depth of moving targets is vital for the deep-sea target detection. Moving targets penetrating into the seafloor sediment always produce large deformation, the Arbitrary Lagrangian-Eulerian (ALE) technique has better grid adaptability and it can solve the mesh distortion generated by moving targets penetrating into seafloor sediment. Therefore, in

ABSTRACT The first Floating Production Storage and Offloading platforms (FPSOs), many still operating in Campos Basin, were converted from single-hull oil tankers. Therefore, collision leading to the FPSO side plating fracture is a serious concern. To simplify the numerical simulation of collision a Platform Supply Vessel (PSV) is modelled assuming a perfectly rigid bow structure, which can deem excessively

ABSTRACT In recent years, reinforced thermoplastic composite pipe (RTP) is widely sought after because of its high strength and corrosion resistance. The development of a connector that is easy to install and highly reliable is essential for the successful application of RTP. In this paper, the mechanical properties of a butt-welding armoured joint between composite pipes were investigated by theoretical

ABSTRACT The proposed paper presents a simplified analytical method for predicting the resistance of ship bottom structure subjected to grounding over a sharp rock idealised as an elliptic paraboloid. During grounding, sharp rock may lead to earlier penetration and serious consequences, such as compartment flooding, oil leakage. Therefore, it is of great importance to assess the response of a ship’s

ABSTRACT This paper presents a two-dimensional simulation model for the idealisation of moored rectangular and trapezoidal floating breakwaters (FB) motions in regular and irregular waves. Fast-Fictitious Domain and Volume of Fluid methods are coupled to track-free surface effects and predict FB motions. Hydrodynamic performance is assessed by a machine learning method based on Cuckoo Search–Least

ABSTRACT This study was performed to examine pile uplift bearing capacity and to develop a novel approach to simulate pile load-settlement response using a new supervised computational intelligence (CI) approach. To reach the planned aim, a series of experimental studies were conducted on concrete piles subjected to uplift loading. . According to the statistical analysis, pile effective length (lc)

ABSTRACT For vessels moving at slower speeds, the frictional resistance contributes up to 80% of the total resistance, demanding a reduction in it. In the BDR/ALS technique, to reduce frictional resistance, the air is injected below the moving body, which is one of the active and interesting research topics. In this work, to reduce the total resistance and the energy required to run a ship, experimental

ABSTRACT Heavy, large and robust supporting structures are needed to keep the airgap clearance of direct-drive multi-MW wind turbine electrical generators open and stable. As rotating pieces of machinery, generators vibrate when their natural frequencies are excited introducing potentially large amplitude oscillations due to the forces acting on them that could cause structural fatigue, noise and,

ABSTRACT Demanding marine operations increase the complexity of manoeuvring. A highly accurate ship model promotes predicting ship motions and advancing control safety. It is crucial to identify the unknown hydrodynamic coefficients under environmental disturbance to establish accurate mathematical models. In this paper, the identification procedure for a 3 degree of freedom hydrodynamic model under

ABSTRACT Extreme storm-safe drilling riser, a solution to overcome high time cost of riser emergency retrieval under the situation of the imminent typhoon arrival, is to modify the existing drilling riser to make it disconnectable and leave the long riser string below in a freestanding mode to survive. The buoyancy can maintains neutral during the normal drilling operation. However, locally the buoyancy

ABSTRACT The present paper introduces the development and verification of two ship performance models which have been implemented in a voyage planning tool designed for summer Arctic operations of commercial vessels. A novel ice resistance estimation algorithm for ice-floe conditions is implemented in the ship performance models. The fuel consumption predicted using both of the models are compared

ABSTRACT Under the actual marine environment, slender risers suffer from external ocean current and internal flowing fluid. When the viscosity of internal fluid is included, the riser’s nonlinear dynamic response is worthy of extra concern. This paper adopts a force-decomposition model to simulate VIV hydrodynamic forces, the embroil force, relative inertia force and Coriolis force induced by internal

ABSTRACT A closed-form analytical solution procedure is proposed to solve the coupled fluid-structure interaction (FSI) equations that involve the first-order Doubly Asymptotic Approximation (DAA1) formulation. An efficient method comprised of the nonstandard finite difference (NSFD) scheme is applied. First of all, analytical equations are developed to analyze the response of a rigid mass-spring oscillator

ABSTRACT Subsea oil production facilities may face extreme or accidental events in association with site-specific conditions. In this paper, qualitative and quantitative assessment for the subsea manifold system is carried out by the fault tree analysis (FTA) method, and the reliability results of the manifold system are also obtained. The proposed approach has achieved the following three objectives:

ABSTRACT In an underwater compressed air energy storage system, fracture of the flexible riser often occurs. To solve this problem, we proposed a static analysis method for a flexible riser based on Cosserat theory. Bending and torsion deformation of a flexible riser were described. Using Euler parameters, static equilibrium differential equations were established. Finite element discretization, finite

ABSTRACT Fast diesel engine models for real-time prediction in dynamic conditions are required to predict engine performance parameters, to identify emerging failures early on and to establish trends in performance reduction. In order to address these issues, two main alternatives exist: one is to exploit the physical knowledge of the problem, the other one is to exploit the historical data produced

ABSTRACT The main objective of this paper is to investigate the bearing capacity behaviour of cracked plates considering low-cycle fatigue (LCF) propagation under cyclic loads. The accumulative plastic damage after crack growth is treated as the residual stress and deformation of the plate. In this study, a cracked plate model is proposed to investigate the difference of its residual ultimate strength

ABSTRACT The dynamic response of a 5 MW floating wind turbine is examined using the coupled finite element simulations, and the dynamic effects of the catenary is considered, while the coupling between flexible components are included. The restoring performance of the mooring-line is analysed based on the vector equations and numerical simulations. The stiffness hysteresis and the influence of the

ABSTRACT In this paper, the novel pendulum tuned mass damper model has been suggested as a potential practical engineering modification to an existing offshore crane setup. A number of potential numerical singularities have been circumvented and substantial numerical model accuracy has been reached. Main application of this study would be extreme value statistics, in case of e.g. extreme weather conditions

ABSTRACT The transient flow behind a bluff body is a common phenomenon in engineering applications. However, most of the research attention is fully developed flow, rather than the initial stages of flow formation. In this work, the transient flow in the initial stage behind a translationally and rotationally started cylinder with multiple control cylinders is investigated by the dynamic mesh method

ABSTRACT Having an accurate prediction of ship roll damping is crucial when analysing roll motions. In this paper, the simplified Ikeda method (SI-method) is compared with the original Ikeda method. The methods are compared using results from a database of roll decay tests carried out on modern merchant ships and a smaller set of predictions in which the original Ikeda method was used. It was found

ABSTRACT The influence of wave force linearisation methods on fatigue damage predictions for jack-up rigs is investigated, using Sesam software as the basis for comparison. The possible risk of significantly underpredicting fatigue damage is highlighted. Dynamic spectral fatigue analysis methodology is applied to a representative jack-up rig in 30 and 70 m water depth in the North Sea. Transfer functions

ABSTRACT Sailing in ice-infested waters has become more relevant for the Royal Netherlands Navy (RNLN). A method is developed to determine the technical safe speed for a single ice floe impact with a typical non-ice strengthened naval vessel. A representative ice floe impact load scenario is applied to three structural arrangements for the side shell structure: a reference design and two alternative

ABSTRACT Short sea shipping poses significant problems for many seafarers, particularly for officers employed in oil tankers as chief officers. This study examines chief officers’ working conditions on short sea shipping. In this study, Simio simulation software was utilised to evaluate the working hours of chief officers. The results demonstrate that the rest periods of the chief officers have been

ABSTRACT For the special ship like catamaran, which has a unique structure with gap resonance, the traditional potential method tends to over-predict the motion at the resonance frequency due to the negligence of fluid viscosity. In this paper, a new method considering damping is put forward to inhibit over-predicted heave and pitch response. Viscous damping is introduced into free surface boundary

ABSTRACT The Electrical Discharge Machining (EDM) process is becoming increasingly used in the shipbuilding industry due to its suitability to produce complex geometries and the machining of materials with high mechanical properties. Although, it is necessary to deepen in its study to be able to adapt it to the own characteristics of the shipbuilding sector, mainly to the high volumes of material to