A hybrid approach to predict the structure-borne noise transmission in ship structures using a waveguide method and Statistical Energy Analysis. The prediction of structure-borne noise transmission in large welded ship structures is required, in order to design maritime vessels with greater ship power and reduced weight, without increasing the noise levels. The aim of this project is to develop a hybrid approach for structural dynamic analyses using an analytical waveguide method and Statistical ....A hybrid approach to predict the structure-borne noise transmission in ship structures using a waveguide method and Statistical Energy Analysis. The prediction of structure-borne noise transmission in large welded ship structures is required, in order to design maritime vessels with greater ship power and reduced weight, without increasing the noise levels. The aim of this project is to develop a hybrid approach for structural dynamic analyses using an analytical waveguide method and Statistical Energy Analysis. The theoretical estimation and associated experimental measurement of the SEA parameters (modal density, coupling and internal loss factors) form the basis for the hybrid approach. The outcomes will result in improved predictive techniques for dynamic analyses of large complex resonant structures.Read moreRead less
Development of Advanced Fracture Mechanics Models and Novel Technical Tools for Integrity, Durability and Safety Assessment. The proposed project will lead to the new understanding of fracture phenomena and structural integrity. It will create a range of novel computer based technical tools for life and integrity assessment of structures in the presence of cracks and other defects, so as to meet the high safety standards across a wide range of industries. The project will result in technology th ....Development of Advanced Fracture Mechanics Models and Novel Technical Tools for Integrity, Durability and Safety Assessment. The proposed project will lead to the new understanding of fracture phenomena and structural integrity. It will create a range of novel computer based technical tools for life and integrity assessment of structures in the presence of cracks and other defects, so as to meet the high safety standards across a wide range of industries. The project will result in technology that will help to make Australian products stronger and more durable so they become more competitive with low cost overseas imports. All the research outcomes will have a direct benefit to Australian interests, including both public and private industries.Read moreRead less
Development of Models for the Three-Dimensional Analysis of Jack-Up Structures. Mobile jack-up structures perform most of the world's offshore drilling in water depths up to 120m, but have a higher accident rate then fixed installations. To improve their safety, this research will develop the framework for the integrated assessment of jack-up behaviour in three dimensions. To achieve this, an advanced plasticity model that describes cyclic behaviour of the circular shallow foundations of jack-up ....Development of Models for the Three-Dimensional Analysis of Jack-Up Structures. Mobile jack-up structures perform most of the world's offshore drilling in water depths up to 120m, but have a higher accident rate then fixed installations. To improve their safety, this research will develop the framework for the integrated assessment of jack-up behaviour in three dimensions. To achieve this, an advanced plasticity model that describes cyclic behaviour of the circular shallow foundations of jack-ups in both clay and sand will be developed and incorporated with random wave loading of seas in a dynamic structural analysis program. The anticipated advantages of the modelling techniques will be assessed against existing two dimensional industry guidelines and monitored field data. Read moreRead less
Aggressive corrosion of steel infrastructure in marine environments. Marine corrosion is known to be aggressive, but how aggressive it can be under long term exposures is the critical question for the safety and economics of much industrial infrastructure, including harbour, coastal and offshore oil industry facilities. Bacterial and microbiological activity is known to contribute. However, recent findings have observed very aggressive corrosion also under sterile and apparently benign condition ....Aggressive corrosion of steel infrastructure in marine environments. Marine corrosion is known to be aggressive, but how aggressive it can be under long term exposures is the critical question for the safety and economics of much industrial infrastructure, including harbour, coastal and offshore oil industry facilities. Bacterial and microbiological activity is known to contribute. However, recent findings have observed very aggressive corrosion also under sterile and apparently benign conditions. No theory to explain these observations currently exists. A new hypothesis is proposed that in certain circumstances second-phase constituents of steels will facilitate autocatalytic corrosion under anoxic conditions. This project investigates the problem and explores mechanisms and conditions. Read moreRead less
Long-term corrosion of offshore steel structures in near-stagnant seawater. This project investigates the seawater corrosion of structural steels under near-stagnant and possibly polluted conditions. Better understanding of long-term corrosion of structural steels in near-stagnant seawaters is needed to predict the safety of steel offshore structures such as the pods supporting wind and wave energy generators. Also, the expensive maintenance of protective coatings and systems could be obviated o ....Long-term corrosion of offshore steel structures in near-stagnant seawater. This project investigates the seawater corrosion of structural steels under near-stagnant and possibly polluted conditions. Better understanding of long-term corrosion of structural steels in near-stagnant seawaters is needed to predict the safety of steel offshore structures such as the pods supporting wind and wave energy generators. Also, the expensive maintenance of protective coatings and systems could be obviated or reduced if corrosion remains acceptable. This project plans to investigate experimentally the temporal development and stochastic nature of general corrosion and pitting for steels under actual near-stagnant seawater conditions. It also plans to build mathematical-probabilistic models for corrosion prediction, calibrated to field data. These models will include allowance for microbiological corrosion effects, important under anthropological pollution.Read moreRead less
Short- and long-term corrosion of steels in highly calcareous seawaters . This project aims to quantify the development of the long-term (25-100 year) protective effect of calcareous deposits on the marine corrosion of mild steels. This is significant because such steels used extensively in major and very expensive coastal and offshore infrastructure. The project outcomes will improve scientific understanding, including the role of microbiological activity. It will develop and calibrate corrosio ....Short- and long-term corrosion of steels in highly calcareous seawaters . This project aims to quantify the development of the long-term (25-100 year) protective effect of calcareous deposits on the marine corrosion of mild steels. This is significant because such steels used extensively in major and very expensive coastal and offshore infrastructure. The project outcomes will improve scientific understanding, including the role of microbiological activity. It will develop and calibrate corrosion prediction models using classical and recently available 100 year data from Europe, the Pacific, Australia and also new project-specific experimental data. These models are expected to be of benefit for Australian engineering consultants in maintain their internationally competitive edge in offshore engineering.Read moreRead less
The influence of sway-roll coupling on the dynamics of an inverted sailing yacht in waves. The ability of a sailing yacht to re-right in waves after capsize will influence the safety of those on board in extreme conditions.
The aim of this project is to incorporate the effects of sway-roll coupling into a numerical simulation of the behaviour of an inverted yacht in waves to assess design features which influence re-righting. Experimental work being conducted during 2001 will be extended to ....The influence of sway-roll coupling on the dynamics of an inverted sailing yacht in waves. The ability of a sailing yacht to re-right in waves after capsize will influence the safety of those on board in extreme conditions.
The aim of this project is to incorporate the effects of sway-roll coupling into a numerical simulation of the behaviour of an inverted yacht in waves to assess design features which influence re-righting. Experimental work being conducted during 2001 will be extended to enable the forces on a model of an inverted yacht in a breaking wave to be determined. and incorporated along with theoretical predictions into the simulation.Read moreRead less
Hydroelasticity of compliant offshore structures. Australia's rich offshore oil and gas reserves are awaiting extensive deepwater extraction. However, there is still a lack of in-depth knowledge in the dynamic behavior of deepwater structures to ensure safe and cost-effective production. We hereby propose hydroelasticity theories and modelling techniques to investigate dynamic fluid-structure interaction problems for compliant offshore structures. We also propose innovative experiments to verify ....Hydroelasticity of compliant offshore structures. Australia's rich offshore oil and gas reserves are awaiting extensive deepwater extraction. However, there is still a lack of in-depth knowledge in the dynamic behavior of deepwater structures to ensure safe and cost-effective production. We hereby propose hydroelasticity theories and modelling techniques to investigate dynamic fluid-structure interaction problems for compliant offshore structures. We also propose innovative experiments to verify the theoretical work. One application is to configure a freestanding compliant tower to suit prospective deepwater oil and gas fields off North-West Australia. Expected outcomes include theoretical and experimental advances in deepwater offshore mechanics and practical computation tools for industry applications.Read moreRead less
Environmental Study of the Wavemaking Characteristics of High-Speed Ferries. The aim is to perform a study of the wave-making characteristics of high-speed ferries of the monohull, catamaran, and multihull type in order to be able to predict their environmental impact on river banks and sea shores. The significance is that a number of ferry services have been curtailed or cancelled as a result of suspected wave damage. The outcome will be a methodology for computing the wave system produced by s ....Environmental Study of the Wavemaking Characteristics of High-Speed Ferries. The aim is to perform a study of the wave-making characteristics of high-speed ferries of the monohull, catamaran, and multihull type in order to be able to predict their environmental impact on river banks and sea shores. The significance is that a number of ferry services have been curtailed or cancelled as a result of suspected wave damage. The outcome will be a methodology for computing the wave system produced by such ferries in water of any depth. The nature of the rate of decay of the wave system will be included in the analysis.Read moreRead less
Optimal nose shaping for delayed boundary-layer separation and transition in axisymmetric flow. The aim of this project is to design a smooth nose for a body of revolution placed in axisymmetric flow of a viscous fluid at high Reynolds number, such that the boundary layer on the body remains unseparated. This can always be done with a sufficiently long nose, but our objective here is to minimise the necessary nose length. Outer potential flows will be provided via ring sources. The potential flo ....Optimal nose shaping for delayed boundary-layer separation and transition in axisymmetric flow. The aim of this project is to design a smooth nose for a body of revolution placed in axisymmetric flow of a viscous fluid at high Reynolds number, such that the boundary layer on the body remains unseparated. This can always be done with a sufficiently long nose, but our objective here is to minimise the necessary nose length. Outer potential flows will be provided via ring sources. The potential flows will be used to determine inner boundary layer solutions. Transition-to-turbulence will be considered by undertaking 2D and 3D stability computations.Read moreRead less