The aim of this paper is in continuation with previous works of other authors, to demonstrate a methodology of analysing unbalanced operating conditions of ship electric energy systems via Millman’s theorem. Its advantages consist in being simple in implementation (either in time domain or in phasor mode) especially by non-electric power engineers, in contrast to the more complicated method via the

Thermal protection in marine electrical propulsion motors is commonly implemented by installing temperature sensors on the windings of the motor. An alarm is issued once the temperature reaches the alarm limit, while the motor shuts down once the trip limit is reached. Field experience shows that this protection scheme in some cases is insufficient, as the motor may already be damaged before reaching

A Proof-of-Concept (POC) low power-low current wireless sensor network (WSN) for corrosion detection and monitoring of offshore wind turbine (OWT)’s component, entitled iWindCr, has been developed and field trialled in one of the OWTs in the UK south region. This paper reports on the setting up and outcomes of this field trial. The trial has successfully demonstrated the working functionality of the

The propulsion demands of high-speed naval vessels often rely on gas turbines, producing significant amount of power achieving thus high performance requirements. Gas turbines can be used either to provide purely mechanical propulsion, or alternatively to generate electricity, which is subsequently used by electric drives to propel the ship. However, the thermal efficiencies of gas turbines are lower

Systems are being developed for power distribution on future navy ships to effectively incorporate advanced electrical systems requiring DC power. These islanded DC microgrids provide new challenges to the management of power flow throughout the system, and thus require advanced controls to accurately regulate and stabilise the systems during changing operational conditions. Therefore, adaptive droop

This paper numerically presented the effect of the cross-flow wake on the hydrodynamic performance of the ship propeller. The propeller is a typical high skewed propeller (HSP) of the training ship ‘Seiun-Maru’, whose experimental data have been frequently used by many researchers. The viscous flow is solved by an incompressible Reynolds Averaged Navier–Stokes (RANS) method using Ansys-CFX solver.

ABSTRACT This paper is aimed to numerically investigate the hydrodynamic and hydro-acoustic behaviours of rotating underwater propeller operating in off-design flow conditions. The performance of the propeller is subjected to significant alteration, as it experiences flow, coming at an angle. For this purpose, numerical simulation is performed for the INSEAN Propeller E779A. Turbulence model based

The presence of sulphur in marine fuel oil relates to health and environmental concerns, as the respective combustion generates sulphur dioxide (SO2). The only method to control this SO2 generation is to limit the quantity of sulphur in the fuel. Shipping activities, although not the main source, contribute around 13% of the total anthropogenic SO2 IMO-3GHG [2015. Third IMO Greenhouse Gas Study, 3rd

The majority of facilities installed in offshore oil and gas fields during the 1980s and 1990s were designed to operate in ‘normal’ conditions. However, during the operational life of the fields, s...

A total of 270 nonlinear steady-state finite element (FE) analyses were performed on 54 FE models of two-planar CHS KK-joints subjected to axial loading at five different temperatures (20°C, 200°C, 400°C, 550°C, and 700°C). The main objective was to study the influence of temperature and dimensionless geometrical parameters on the ultimate load, failure modes, and initial stiffness of the KK-joints

The current paper presents a simple mathematical model for replication of the transient acceleration motion of displacement hulls in calm water under the action of a propulsion system. Different empirical methods are coupled, and an operational speed problem is solved in the time domain. The resistance of the ship is calculated by using the Holtrop method. The values of thrust force, torque and propeller

Ballast water management and treatment is an on-going issue for marine industry including small and bulk carriers, cruise ships, passenger ships and cargo vessels. Several regulations are implemented at regional, national and international levels to minimise the environmental impacts related to improper disposal of contaminated ballast water at ports. In this study, an environmentally benign approach

Stringent regulations and policies have prompted vessel operators and owners to direct the interests on developing greener vessels from oil-fuelled vessels to LNG-fuelled vessels. Consequently, the increasing demands for LNG, as the alternative fuel for vessels, have led to the booming development of LNG carriers or bunker vessels. LNG transfer operations, including loading and bunkering operations

Pipeline repair plays an important role in safe pipeline operation. Composite material repair technology has been widely used in pipeline repair due to its advantage of light weight and low cost. I...

This paper presents a vision system designed for an underwater robot to facilitate measuring the distance to an inspected surface and its orientation with respect to the robot. The system uses a se...

This article describes the development of the boundary element method (BEM) to predict the partially submerged propeller (PSP) performance with and without the cup effect, and the 3D unsteady venti...

The article describes research into the use of acoustic emission elastic waves (AE) for diagnosing insulated-gated bipolar transistors (IGBTs). Currently used in many modern shipboard power electronic systems, IGBTs are crucial components required to operate with extreme reliability. The acoustic emission elastic waves method was used to determine the acoustic signals of switching transistor and can

The aim of this research project was to determine the rate at which oxygen depletes in enclosed spaces. Cargo holds, chain locker and double bottom tanks are only some of the enclosed spaces found on a ship. The project was conducted using oxygen depletion experiments on scrap metal in sealed and open vented containers. In addition, the speed of oxygen depletion in a replicated chain locker is investigated

Abstract A lifting motor pump for deep-sea mining was proposed as a researching object. First, the structure and design method of this pump was introduced. Second, the simulating computations of the impeller in this pump were conducted at different working processes. Finally, the experiment of a two-stage lifting motor pump was conducted in the process of work to prove the applicability of this new

This Naval Engineering and Ship Control special edition of the Journal of Marine Engineering and Technology aims to present cutting edge research on naval engineering and ship control, as was prese...

ABSTRACT Exhaust Gas Recirculation (EGR) was recently introduced in large marine two-stroke diesel engines to reduce -emissions. Controlling EGR flow during accelerations, while keeping good acceleration performance is challenging, due to delays in the scavenge receiver oxygen measurement and upper limits on fuel for avoiding black smoke. Previous oxygen feedback controllers struggled during accelerations

ABSTRACT Recent developments have rendered the Dual Fuel (DF) engines an attractive alternative solution for achieving cost-efficient compliance to environmental regulations. The present study focuses on the safety investigation of a marine DF engine in order to identify potential safety implications. This investigation is based on an integrated engine model, which was developed in GT-ISE™ software

ABSTRACT The proposed paper presents the design and development of the combined guidance and control strategies for the autonomous navigation of unmanned vessels characterised by azimuth-based thrust architecture. Autonomous marine vehicles (AMVs) are consolidated technological tools commonly employed for different tasks such as exploration, sampling and intervention. With the final aim of autonomous

Studies have been being carried out to make production faster and more organised in the shipbuilding industry, as in other industry. The fact that automation-based works are limited in the shipbuil...

Previously, the action factors, which are generally used in the region of Malaysia is based on the data from the Gulf of Mexico (GoM) or the North Sea, where the environmental condition is much harsher than the offshore Malaysia. Direct application of the high load factors in these regions can result in a waste of economic resources. Based on a reliability-based Load and Resistance Factor Design approach

ABSTRACT The traditional way to underwater thrust vectoring is mainly based on a specially designed mechanical system which provides the propulsion system additional degree of freedom. This method is effective in field applications. However, there are several drawbacks such as complex structure and large dead weight. In this paper, a new type of thrust vectoring method, based on inflated surface is

ABSTRACT The paper presents a collision avoidance algorithm for ship open sea navigation, based on an ad hoc modified version of the Rapidly-exploring Random Tree (RRT*) algorithm. The proposed approach is designed to act as the high level layer of the navigation control structure for an autonomous ship. Collision and grounding still represent the primary source of sea accidents, thus an automatic

ABSTRACT The U.S. Navy is investing in the development of new technologies that broaden warship capabilities and maintain U.S. naval superiority. Specifically, Naval Sea Systems Command (NAVSEA) is supporting the development of power systems technologies that enable the Navy to realise an all-electric warship. A challenge to fielding an all-electric power system architecture includes minimising the

ABSTRACT Electric systems for naval applications create a challenge for the power system associated control. When incorporating loads with a high-power ramp rate within what is essentially an islanded microgrid, energy sources that supplement generators must be used due to the ramp rate constraints of the generators; this is where energy storages play a key role. A higher-level control layer is needed

ABSTRACT This paper investigates the flow field around the KRISO Very Large Crude Carrier (KVLCC2) model at different drift angle using the RANS method in combination with the Re-Normalization Group (RNG) and Shear Stress Transport (SST) turbulence models. The hydrodynamic forces and yaw moment acting on the KVLCC2 model are calculated under the different turbulence models and drift angles, and the

As global warming is causing a significant reduction in the extent and the thickness of Arctic sea ice, a narrative for future large-scale commercial shipping in the Arctic has started to evolve. H...

ABSTRACT Vulnerability reduction is an important topic during the design of naval ships because they are designed to operate in hostile environments and because their on-board distributed systems are becoming increasingly complex. The vulnerability needs to be addressed in the early design stages already, in order to prevent expensive or time-consuming modifications in later, more detailed design stages

Ports are complex systems that play a crucial role in the transportation of maritime-related products and services. Since ports face various safety issues in design, installation, operation and maintenance processes, there are many aspects open for improvement in Occupational Health and Safety risk assessment and it is required to deal with risks, reduce them to an acceptable level and control. To

In the study, the dynamic analysis of the engine piston assembly was compared with the experimental measurements and the stable working speed was tried to be determined. The theoretical model was developed in addition to the experimental results. The relationships between the forces and torques applied in the crank mechanism, such as gas force and inertial force, are properly addressed. In the stationary

The current research was a comparative study of reinforced ceramic particles and mixing proportion on the microstructural and slurry erosive characteristics for fabricated composites. Dual reinforced particle composites were fabricated by adding combinations of numerous wt% of titanium carbide (TiC) and zircon sand (ZrSiO4) to aluminium die-casting (ADC12) alloy matrix composites. ADC12 alloy composite

In this paper, a single-stage, horizontal type centrifugal pump, which can be used in a chemical tanker’s cargo operations, was modelled with MATLAB/Simulink software. The modelled pump was run wit...

This paper addresses the reliability aspects regarding deck machinery on ageing/aged fishing vessels. A reliability and degradation analysis for ageing fishing vessel deck machinery enables an eval...

Each vessel has its own way of sailing in the port region. Any autonomous vessel navigating such a scene should be able to predict the trajectories of surrounding ships and adjust its behaviour to ...

This paper presents a methodology for the development and installation of an electric power quality monitoring system onboard a ship, for managing and optimising the electric power of critical load...

The safe operation of marine turbine generators is a crucial concern in industries and academics. It is always important to monitor the health status of marine turbine generators. The lubricant oil usually carries abundant information on the turbine operation conditions. Various oil parameters of the turbines have been used in the existing monitoring systems. However, many of them conflict with each

Nowadays, shipping industry faces challenges of energy efficiency and reducing of fuel consumption. Moreover, Waste Heat Recovery Systems (WHRS) regarding energy efficiency have a larger focus to utilise the heat energy lost from all thermal processes from ship engines. WHRS is one of the best methods to reduce fuel consumption and implicitly emissions. Refrigeration system, which can be evaluated

As one of the most critical vessel motion, heave motion will lead to the great tension at the top end of a steel catenary riser (SCR), and can also result in the compression buckling and large bending moment in the touchdown zone (TDZ). The purpose of this study is to investigate the motion transfer rule of top-end heave excitation along catenary risers and explore the underlying correlation between

This paper presents a numerical investigation on the hydrodynamic performance of sandglass-type FPSOs with four different cross sections. In order to estimate the hydrodynamic performance and utilise the results in the design stage of FPSOs, a frequency-domain numerical simulation program, ANSYS/AQWA software package, has been used. Numerical results were compared with experimental data and good agreement

ABSTRACT The present article compares the effectiveness of two chemical compounds to reduce the growth of biofilm adhering to the tubes of a heat exchanger-condenser refrigerated by seawater. The compounds tested in the study were: a quaternary ammonium compound (QAC) and an aliphatic amine (triethanol amina, TA). Each biocide was applied intermittently in a first shock stage and in a second stabilising

This paper presents mechatronic design and hierarchical locomotion control of a biomimetic robotic fish for three-dimensional swimming modes. Inspired by biological features of Lamprey, a closed lo...

Subsea cables protection afforded by burying a cable [beneath the sea bed] also means that the available methods for their survey are drastically reduced. From the existing methods only electromagn...

This paper investigated the benefits of vibration performance of diesel generator set (D/G-set) employing a kind of novel anti-vibration structure known as an inerter-rubber vibration isolator. We designed this vibration isolator in parallel with a rubber-part and a ball-screw inerter. Based on the inerter-rubber vibration isolator, the vibration system of an existing D/G-set (5DK-20) was built, and

Pressure sensor used in marine hydrographic survey is an important device for the deep sea detection, the tsunami forecast and the marine engineering. Owing to its mature technology process and low production cost, silicon piezoresistive sensor is widely applied in the field of industrial pressure measurement. However, its temperature effect can result in non-negligible dynamic error, which cannot

India is the fourth biggest electricity consumer on the planet after the United States, China and Russia. India’s energy strategy concentrates on securing energy sources to address the issue of its...

Submarine piggyback pipeline is an important tool for oil and gas transport, especially, in the marginal oil field. When the scour happens in the seabed, the pipeline slides easily, which may cause the pipeline failure. The dynamic slope angle is one of the most important characteristics of the scour. In this work, the dynamic slope angles of the sandy seabed under piggyback pipelines in steady flow

ABSTRACT Ring-stiffened circular cylindrical shells are commonly used in many engineering applications. In the present study, the strength and stability characteristics of ring-stiffened circular cylindrical shells are investigated using self-organising map (SOM) technique and multivariate approaches. Stress and critical pressure analysis of ring-stiffened circular cylindrical shells under hydrostatic

Sensor data from marine engine systems can be used to detect changes in performance in near real time which may be indicative of an impending failure. Thus sensor-based condition monitoring can be important for the reliability of ship machinery systems and improve maritime safety. However, there is a need for efficient and robust algorithms to detect such changes in the data streams. In this paper

Vortex induced vibration (VIV) is of practical interest since it can result in the fatigue damage of structures, so has been a highly researched topic during the past few decades. The present study employs the unsteady Reynolds-Averaged-Navier–Stokes (URANS) equations combined with the shear-stress transport (SST) k-ω turbulence model to carry out the numerical simulation of the two-degree-of-freedom

Underwater acoustic sensor network (UASN) is an emerging technology meant for underwater explorations. In underwater communication, the acoustic signal travels a longer distance with smaller bandwidth. Characteristics of the acoustic channel and the distance between underwater sensor nodes vary with time due to the variations in the water current. This affects the channel quality as well as the topology

This paper proposes a nonlinear robust track keeping control algorithm for energy efficiency from the perspective of ship motion control, based on the great significance of the twenty-first Century Maritime Silk Road. Replacing the course error with the driven by the sine function in course keeping loop to serve as the input of the controller, the simulation results tested on the ship autopilot simulation

ABSTRACTAmong the effective solutions for the reduction of environmental pollution, the use of fuels with limited-sulphur content or bio-based fuel has been paid much attention due to their advanta...

ABSTRACTThis paper presents an approach to the calculation of unbalanced fault currents in shipboard power systems based on the application of Millman’s theorem. A full analysis of the time-variant...

Deep-sea hydrothermal source investigation utilising water and gas samples to characterise ocean resources requires water sampler, both large and small volume. How to preserve the original captured samples in the sampler during its lifting process to the surface remains challenging. Our research develops a piston type deep-sea pressure equaliser installed in the sampling bottle to solve the pressure

The engine rooms of ships accommodate different machinery systems that are critical to ship operations. For these critical machinery systems to continue delivering the high level of service, operat...

This paper first assesses the operational uncertainties of a particular piece of equipment in a marine and offshore system based on an oil analysis technique. Trend analysis, family analysis, environmental analysis, human reliability analysis and design analysis for each criterion are aggregated using evidential reasoning (ER) and analytical hierarchy process (AHP) algorithms. Data is collected from