Inspired by the novel flapping caudal fin and body undulatory mechanisms in nature swimmers, simplified physical models are built in Computational Fluid Dynamic(CFD) solvers, and used to investigate the self-propulsion performance under different conditions with various kinetic and geometric parameters. Two simplified physical models, three-dimensional flapping wing model with flexibilities in lateral and rotational directions and multi-body system model with rigid components connected by revolute joints, are investigated for mimicking typical bio-inspired locomotion. The study was firstly carried out on a three-dimensional wing with a freedom intranslational direction under a prescribed flapping motion. The investigation focused on how the system kinematics and structural parameters affect the dynamic response of a wing with a relatively small span length. It shows that the induced wing motion is a result of the system stability breakdown, which has only been observed by previous researches in the two-dimensional case. The results obtained indicate that the evolution of the wing locomotion is controlled not only by the flapping frequency and amplitude, but also influenced by the system inertia as well as the wing aspect ratio and density ratio. Moreover, initial perturbation effect on wings flexibility plays a role in the evolution development. Subsequently, a comprehensive investigation is carried out on the dynamics response of a three-dimensional flapping wing with two degree of freedoms in lateral and rotational direction under a zero initial velocity condition. Distinguishing from the limited existing studies, present work performs a systematic examination on the effects of wing aspect ratio, inertia, torsional stiffness and pivot point on the dynamics response of a low aspect ratio rectangular wing under an initial zero speed flow field condition. The reduced rotational pitching help with the symmetry breakdown of the flapping wing and results in a forward/backward motion. When the wing reaches its stable periodic state, the induced pitching frequency is identical to its forced flapping frequency. However, depending on various kinematic and dynamic system parameters,(i.e. flapping frequency, density ratio and pitching axis), the lateral induced velocity shows a number of different oscillating frequency. Furthermore, compared with one degree of freedom wing in lateral direction only, the propulsion performance of such a two degree of freedom wing relies very much on the magnitude of torsional stiffness adding on the pivot point, as well as its pitching axis. In all cases examined, thrust force and moment generated by a long span wing is larger than that of a short wing,which is remarkably linked to the strong reverse von Kármán vortex street formed in the wake of a wing. In a separate study, the undulatory motion of fish body is mimicked with a series of linked rigid bodies, i.e. a multi-body system. The connection between two adjacent rigid components can be modelled as the revolute hinge joint, with either a passively induced pitch motion or actively prescribed pitch motion. Emphasis is put on the development for solving the problems of coupling multi-body dynamics with fluid dynamics by implementing Mobile Multi-body System (MMS) algorithm with CFD solver. Verifications are carried out by repeating the previous work, and innovative cases are tested on a prototype with three-linked rigid body system with an active joint and a passive joint. The investigation is made on the flexibility effect of tail on the propulsion performance. It shows there are optimized stiffness and damper coefficients at the passive joint leading the most efficient propulsion and fastest velocity through varying the posture of undulatory trajectory.

The ever-growing intercontinental maritime trade and transporthave identified the need for the ship and passengerssafety, energy efficiency and environmental pollution to be considered as dominant issues within shipping industry and academia. Recently introduced safety regulations, known as Safe-Return-to-Port, and ‘green’ regulations, by the IMO, came into force to address and, indirectly, couple the above objectives through the enforcement of specific safety performance requirements of ship systems after a casualty and mandatory environmental measures for GHG emissions limitation, for the former and the latter regulations respectively. This thesis focus is on improving the safety and the energy efficiency of ships during design and operation by adopting approaches assessing the safety critical systems availability at emergencies and estimating performance requirements of electrical energy onboard ships over their life cycle. Through the adoption of methodologies successfully applied in damage stability, the probabilistic assessment of systems safety is employed with the logical modelling of the system into the ship environment and the application of statistical flooding damages to be initiated. Critical zones for the systems location are investigated with topological and geometrical optimisation to be performed identifying ‘enhanced-availability areas’ onboard targeting, also,the components redundancies reduction. First principles were introduced for the numerical modelling of the electrical energy systems onboard aiming to evaluate the energy performance of the ship. However, the great number of input parameters and computational problems shown up during the systems development, especially for larger vessels such as passenger, triggered necessary simplification considerations for the design. Investigation was considered for the identification of the key design parameters, with a verification process based on energy simulations to have been used for constructing guidelines and indicating acceptable assumptions. Investigation results were used for the systems optimisation in energy efficiency and cost perspectives during the design through the development of the Power Management System, with the latter’s functionality to be extended also during operation aiming fuel consumption minimisation. The amount of consumed fuel were quantified for both case, and results were used to create design and operation guidelines for power generation sets sizing and loading respectively. All findings were used to form methodology for the design of the electrical energy systems aiming to increase the energy efficiency through the appropriate sizing of the power generation sets and also, for the case of passenger vessels, to increase systems safety through the optimisation of their onboard location. Implementation of the methodology was exhibited with two case studies, one for a cargo and one for a passenger ship. The work undertaken and the derived results clearly demonstrate the applicability of probabilistic assessment for the quantification of systems availability post-casualty not only for rules compliance but also for the increased results accuracy and the integration to ship survivability concept. In addition, the introduction of Dynamic Energy Modelling concept as a platform in shipping to support life-cycle energy management were concluded through the electrical energy systems simulations during operation and design considering simplification during the latter’s process. Those concepts could be applied under the multi-objective optimisation platform in order to explore the whole design space concerning systems common parameters. All these constitute significant developments in shipping.

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The missions being proposed for autonomous underwater vehicles (AUVs), by both marine scientists and industry, are becoming increasingly complex and challenging. In order to meet these demands the next generation of AUVs will need to be faster, operate for longer and be more manoeuvrable than existing vehicles. It is therefore vital that the hydrodynamic forces and moments acting on a self propelled manoeuvring AUV can be predicted accurately at the initial design stage. The flow around a typical AUV is both turbulent and three dimensional with significant interactions between the hull, propeller and control surfaces. An unsteady computational fluid dynamics analysis based on the Reynolds Averaged Navier Stokes (RANS) equations is too expensive for AUV design. In order to capture the action of the propeller at an acceptable computational cost, a novel method of coupling a commercial RANS solver with a body force propeller model based on blade element momentum theory has been developed. This discretises the propeller plane into a series of radial and circumferential sectors. The local axial and tangential inflow conditions at each sector of the propeller plane can then be considered. This allows analysis of non-uniform propeller inflow conditions due to the interaction of hull, propeller and control surfaces. During a manoeuvre the hull boundary layer may separate due to the adverse pressure gradient, resulting in free vortex sheets which roll up to form a pair of body vortices. An adaptive mesh strategy is required to ensure a suitable mesh structure and density to capture these flow features. Modifications to a vortex capture algorithm (VORTFIND) are proposed, optimising it as a tool for identifying the path of vortex structures. This enables it to be used as part of an iterative meshing strategy, capturing vortical flow features more accurately and consequently their influence on the pressure loading experienced by the hull. To demonstrate the pertinence of the numerical methods developed in this work a series of case studies has been analysed. These include: determining the hydrodynamic derivatives of an AUV, propeller-rudder interaction studies, steady state manoeuvring performance of the self propelled KVLCC2, and in-service straight line performance prediction of Autosub 3. These highlight the roles of the numerical methodologies in the design process for future AUVs. The techniques developed in this work enable the designer to accurately predict the hydrodynamic loading acting on a self propelled manoeuvring AUV

A study into the environmental impact of marine power systems was performed in proximity with the defined research objectives: (i) present an overview on Annex VI The International Convention for the Prevention of Pollution from Ships, cargo ships, marine power systems and technologies; (ii) review life cycle assessment (LCA) methodology development; (iii) develop an LCA framework for marine power systems; (iv) carry out case studies to determine environmental impact, significant components and critical processes; (v) apply scenario analysis to investigate the sensitivity of the results to selected parameters; and (vi) compare power systems under study to verify their environmental benefits. Built upon literature and the proposed LCA framework, LCA case studies on conventional, retrofit and new-build power systems were performed using a bottom-up integrated system approach, where data were gathered and LCA models were created for individual technologies using GaBi software. Life cycle impact assessment was performed using CML2001, International Reference Life Cycle Data System (ILCD) and Eco-Indicator99 to estimate the environmental impact of the systems. It was found that disposing metal scrap of significant components was the principal cause of ecotoxicity potential, which was the impact category that showed the top two highest indicator results; and operating diesel engines and auxiliary generators or diesel gensets was mainly accounted for other impact categories. When compared with the conventional system, both retrofit and new-build systems consumed less fuels and released less emissions during operation but involved more materials and energy during other life cycle phases, leading to a decline in most impact categories to the detriment of a few burdens. The life cycle of marine power systems must be planned, managed and monitored appropriately for reduced environmental implications. Further research should address limitations presented in this study and explore other factors that might affect the environmental burdens of marine power systems.

Liquefaction of fine particle cargoes such as unprocessed nickel ore and iron ore, resulting in cargo shift and loss of stability of ships, has caused the loss of many lives in marine casualties over the recent few years. Since the dangers of cargo liquefaction have long been known to the shipping industry, the question of why the phenomenon is resurfacing now would be a legitimate one. Under the requirements of International Maritime Bulk Solid Cargoes (IMSBC) Code adopted by the Maritime Safety Committee of the Organization, the moisture content of the cargo that may liquefy shall be kept less than its Transportable Moisture Limit (TML) in advance of loading, as determined from one of three laboratory test methods specified in IMSBC code. However, the accuracy of these methods is still not understood and the TML result varies particularly when conducted in different laboratories or in different methods for a given sample (Rose, 2014). Considering the ambiguity of testing (unavailability or non-compliance) and the variability in cargo properties and state as well as conditions that can lead to liquefaction (pertaining to ship design and operation and to environmental conditions), it is necessary to investigate the root causes that trigger the phenomenon and address the problem in a comprehensive manner. On the other hand, despite the positive steps that have been taken towards prevention of such shipping accidents, IMSBC code appears to have certain limitations and leaves the shipper responsible to involve the competent authority and the operator for the characterization of the cargo and the hazards it entails for the ship and its crew, if in doubt. This thesis, therefore, gives consideration to the development of the numerical simulation method to the ship cargo liquefaction, which could be feasibly used as a reference and possibly support a suitable regulatory framework for the liquefaction analysis of cargoes.

There is no doubt that recent years, maritime industry is moving forward to novel and sophisticated inspection and maintenance practices. Nowadays maintenance is encountered as an operational method, which can be employed both as a profit generating process and a cost reduction budget centre through an enhanced Operation and Maintenance (O&M) strategy. In the first place, a flexible framework to be applicable on complex system level of machinery can be introduced towards ship maintenance scheduling of systems, subsystems and components. This holistic inspection and maintenance notion should be implemented by integrating different strategies, methodologies, technologies and tools, suitably selected by fulfilling the requirements of the selected ship systems. In this thesis, an innovative maintenance strategy for ship machinery is proposed, namely the Probabilistic Machinery Reliability Assessment (PMRA) strategy focusing towards the reliability and safety enhancement of main systems, subsystems and maintainable units and components. In this respect, the combination of a data mining method (k-means), the manufacturer safety aspects, the dynamic state modelling (Markov Chains), the probabilistic predictive reliability assessment (Bayesian Belief Networks) and the qualitative decision making (Failure Modes and Effects Analysis) is employed encompassing the benefits of qualitative and quantitative reliability assessment. PMRA has been clearly demonstrated in two case studies applied on offshore platform oil and gas and selected ship machinery. The results are used to identify the most unreliability systems, subsystems and components, while advising suitable practical inspection and maintenance activities. The proposed PMRA strategy is also tested in a flexible sensitivity analysis scheme.

The introduction of the IMO Performance Standard for Protective Coatings (PSPC) for dedicated water ballast tanks (WBT) has increased the importance of the coatings applied in these tanks. Typical structural configurations within Water Ballast Tanks (WBTs) have a high degree of complexity; these spaces contain a large extent of edges, corner details and welds, which are commonly cited as areas most likely to suffer coating failure. However there is no quantitative measure of complexity as an indicator of how difficult a structure is to coat reliably. The concept of ‘structural complexity’ is considered with the intention of improving the in-service performance of applied coatings by proposing ships structures that include the coating process as a design consideration. As a means to try and provide a quantitative measure indicative of how easy a structure is to coat, the idea of ‘structural complexity’ is developed based on fundamental structural features. This measure is then used to understand the influence that different stiffener profiles and stiffener spacing may have on the coating process if structural configurations are sought that have reduced complexity. Investigation of the principal developments of the coating process indicates that any improvement is unlikely to be driven by coating technology or process alone. If improvements are to be made the suggestion here is that they should be driven by improving the design of the structure to be coated. The intention is to promote a ‘design for the coating process’ methodology to achieve this. The global ship and structural design process have been reviewed, where the classical approach looked at the relationship between weight and strength. This work concurrently considers the implications of different structural configures on not only weight and strength but also ease of coating. The relationship between the topology of the structure and the physical task of applying paint to it has formed the foundation of a ‘design for coating’ methodology, where the influence of structural complexity on all aspects of performance is considered with equal merit. A coating cost estimator has been developed in order to demonstrate the potential savings that could be realised by considering the coating process during the design phase. A simple optimisation routine has been used to seek solutions for minimum, complexity, weight, steelwork and coating costs. This allowed the balance to be explored between the completing aspects of the steelwork and coating processes. These alternative design solutions have been assessed using mathematical computational methods to ensure that the designs provide adequate structural performance.

Behaviour of two cylinders in tandem subjected to a stream of steady uniform flow is investigated. This research includes experimental and mathematical simulation so that a better understanding of the interaction between two bodies undergoing vortex induced vibration (VIV) can be achieved while one is submerged in the wake of the other. Amplitude and frequency of oscillation are observed for both cylinders when they are placed at different distances from each other. Positioning cylinders at various spacings can help to shed some light on the interaction mechanism of the upstream wake and trailing cylinder. An experimental investigation was carried out in sub-critical Reynolds number and low mass-damping to simulate the conditions in which offshore structures are deployed. Initially, two identical cylinders are placed in-line with the stream at various spacings. The response of leading cylinder is observed to be similar to that of an isolated cylinder experiencing VIV at all spacings. On the other hand, trailing cylinder response is observed to increase with flow velocity at small and medium spacings. Moreover,as the spacing grows large downstream response becomes more similar to that of the leading cylinder. Motion trajectory of trailing cylinder is significantly influenced by the leading body, and does not follow the typical figure of eight observed for an isolated cylinder at all velocities. Frequency power spectrum of obtained time histories reveals that two sources of excitation exist for trailing cylinder. Corresponding motion to each excitation source is determined using Fast Fourier Transform. The second set of experiment was conducted using similar cylinders with different natural frequencies to observe how it influences the interaction between two cylinders. It was observed that behaviour of trailing cylinder alters in comparison with initial set up. However, two sources of excitation are still detected in this set-up. Mathematical simulation is pursued by modelling the oscillating cylinders with a simple mass-spring-damper system. Furthermore, the force exerted to cylinders by wake is simulated by wake oscillators which can capture the self-exciting and self-limiting nature of VIV phenomenon. Two equations are coupled together by assuming that wake force is proportional to cylinder acceleration. Then, the system of equations is solved analytically,and results are compared to those obtained by a SimuLink model of the system. SimuLink model is solved by numerical RungeKutta method. It was observed that model is successful in simulating leading cylinder vibration amplitude,while it, initially, fails drastically to predict the oscillation amplitude of trailing cylinder due to buffeting vortices. Two terms were added to accommodate the effect of upstream wake on the trailing cylinder, to modify the force in the equation of motion which is respectively proportional to acceleration and velocity of the cylinder. Moreover, acceleration term is determined by fitting a linear function of the variable to the difference between upstream and downstream wake force obtaining from the experimental investigation results. Additionally, the damping term is determined by optimization of variance between simulation and experiment results. Such an observation can confirm that upstream turbulent wake has a significant influence on added mass coeffcient of the trailing cylinder which both are observed to be dependent on upstream Strouhal number. Overall, the agreement between mathematical model and experimental results is evaluated for both cylinders. Model error for trailing cylinder is calculated between 20% to 30% in cross-flow direction. This error is lower than that of the leading cylinder which is a well established method in literature for simulating VIV of an isolated cylinder.

The thesis examines the place of art and design in the life of the Peninsular and Oriental Steam Navigation Company (P&O). In particular, the thesis examines P&O’s art and design in the context of the company’s evolving role in the networks of the British Empire and Commonwealth from the company’s foundation in 1837 to the closure of its liner service in 1969. This contributes a different perspective to existing debates which have not yet focused on the role of everyday corporate art and design in Victorian maritime empire, the persistence of maritime empire in twentieth century art and design, or the impact of decolonisation on Britain’s maritime identity and culture after 1949. Drawing on P&O’s business archive held at the National Maritime Museum, Greenwich, the thesis illustrates the case for a nuanced view of imperialism and culture beyond the simple monoliths of good and evil, and beyond generic characterisation as either corporate pride or propaganda. The research demonstrates how Britain’s imperial-maritime culture adapted a variety of art and design forms and functions at different times and places in the nineteenth and twentieth centuries. It reveals a story of imperial change, instability and uncertainty, as much as it does corporate power, order and control. The extended post-colonial timeframe identifies how melancholic and nostalgic imperial echoes persist and return in corporate narratives long after the formal end of the Empire.