Viscous extensional flow and drop breakoff. Honey falling from a spoon is an everyday example of a viscous fluid in a free extensional flow which may eventually break up into drops. Such flows are important in modern technologies including ink-jet printing, welding, soldering and molten metal processing, polymer and glass fibre spinning, and for rheological measurement. We seek to increase understanding of the mechanisms governing such flows, particularly the role of initial conditions and the ....Viscous extensional flow and drop breakoff. Honey falling from a spoon is an everyday example of a viscous fluid in a free extensional flow which may eventually break up into drops. Such flows are important in modern technologies including ink-jet printing, welding, soldering and molten metal processing, polymer and glass fibre spinning, and for rheological measurement. We seek to increase understanding of the mechanisms governing such flows, particularly the role of initial conditions and the geometry of the original containing vessel, together with balances between forces such as inertia, gravity, viscosity, viscoelasticity, and surface tension, through a theoretical, computational and experimental study of the fluid mechanics.Read moreRead less
A novel approach to controlling boundary-layer separation. This project will involve fundamental research into the control of the fluid dynamical phenomena of boundary-layer separation and transition to turbulence. The project will be built upon a firm foundation of mathematical modelling of the complex behaviour of fluid flows that are near the onset of flow separation or turbulence. The project will produce results that will permit the development of control strategies that can be implemented ....A novel approach to controlling boundary-layer separation. This project will involve fundamental research into the control of the fluid dynamical phenomena of boundary-layer separation and transition to turbulence. The project will be built upon a firm foundation of mathematical modelling of the complex behaviour of fluid flows that are near the onset of flow separation or turbulence. The project will produce results that will permit the development of control strategies that can be implemented in a wide variety of important technological applications, such as drag reduction in the aerospace and ship industries as well as the control of stall (or loss of lift) in modern aircraft.Read moreRead less
Robust fluid mixing through topological chaos. The Australian chemicals and plastics industry has an annual turnover of over $20 billion and employs over 77,000 people; fluid mixing is fundamental to this industry, yet the industry is recognised as underinvesting in research and development in this essential area. Furthermore, frontier technologies such as biotechnology and the next generation of smart materials also crucially rely on fluid mixing. This project aims to evaluate a new paradigm ( ....Robust fluid mixing through topological chaos. The Australian chemicals and plastics industry has an annual turnover of over $20 billion and employs over 77,000 people; fluid mixing is fundamental to this industry, yet the industry is recognised as underinvesting in research and development in this essential area. Furthermore, frontier technologies such as biotechnology and the next generation of smart materials also crucially rely on fluid mixing. This project aims to evaluate a new paradigm (topological chaos) for the design of mixers, to provide better and more robust mixers that work from microscopic to industrial scales.Read moreRead less
Systematically model the large-scale complexity of turbulent floods and thin film flows. This project continues development of new models, and computer
simulation, of turbulent flood, river and estuarine flow. The models
will be based systematically upon established turbulence models to
resolve accurately the complex physical processes. The development of
new and robust computer models for thin layers of coating fluid will
aid many industrial processes. We also aim to provide correct ini ....Systematically model the large-scale complexity of turbulent floods and thin film flows. This project continues development of new models, and computer
simulation, of turbulent flood, river and estuarine flow. The models
will be based systematically upon established turbulence models to
resolve accurately the complex physical processes. The development of
new and robust computer models for thin layers of coating fluid will
aid many industrial processes. We also aim to provide correct initial
conditions and boundary conditions for simpler cases of the above
flows. The approach leads to a greater understanding of the range of
applicability of the models through better estimating the errors in the
modelling process. The project develops a fundamental enabling
methodology for engineering and the sciences.
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A theoretical investigation into the effect of nonlinear wave interactions in promoting transition-to-turbulence. The problem of transition-to-turbulence remains one of the fundamental unanswered questions in fluid dynamics. An understanding of the processes leading to transition is necessary if the active control of turbulence is to be achieved. This project will focus attention on a new class of waves, which have only recently been described the CI, in order to determine how they are triggered ....A theoretical investigation into the effect of nonlinear wave interactions in promoting transition-to-turbulence. The problem of transition-to-turbulence remains one of the fundamental unanswered questions in fluid dynamics. An understanding of the processes leading to transition is necessary if the active control of turbulence is to be achieved. This project will focus attention on a new class of waves, which have only recently been described the CI, in order to determine how they are triggered and how they may serve to actively promote the early development of turbulence in a broad class of fluid flows.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
Assessment of the aerodynamic behaviour of fibrous particles under well-defined conditions of relevance to bio-fuel combustion. Biomass is plant-derived fuel, which has the advantage of being greenhouse neutral. Biomass can potentially be utilised both in existing combustion technologies, after minor modifications, and in purpose-designed combustors. It is typically fed into a furnace or boiler as shredded particles, (e.g. of wood, straw or bagasse), with jet(s) of air, either alone or as part ....Assessment of the aerodynamic behaviour of fibrous particles under well-defined conditions of relevance to bio-fuel combustion. Biomass is plant-derived fuel, which has the advantage of being greenhouse neutral. Biomass can potentially be utilised both in existing combustion technologies, after minor modifications, and in purpose-designed combustors. It is typically fed into a furnace or boiler as shredded particles, (e.g. of wood, straw or bagasse), with jet(s) of air, either alone or as partial replacement of pulverised coal. However these particles are fibrous and, unlike round particles, their aerodynamic behaviour in such systems is poorly understood. The project will provide new understanding, data and models necessary to maximise efficiency and minimise emissions from the utilisation of these fuels.Read moreRead less
Topological Optimisation of Fluid Mixing. The proposed research is aimed at improving the efficiency of fluid mixers,
which in the long term has potential to reduce vastly the economic and
environmental costs associated with large-scale mixing processes in Australian
chemical industries. The research will not only impact on practical mixer
design, but will also develop important results in the application of topology
to the the field of chaotic dynamical systems. This project will also prov ....Topological Optimisation of Fluid Mixing. The proposed research is aimed at improving the efficiency of fluid mixers,
which in the long term has potential to reduce vastly the economic and
environmental costs associated with large-scale mixing processes in Australian
chemical industries. The research will not only impact on practical mixer
design, but will also develop important results in the application of topology
to the the field of chaotic dynamical systems. This project will also provide a
graduate student and post-doctoral researcher with training to pursue a career
in fluid dynamics or general applied mathematics research.
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A new angle on the coalescence of drops. Many processes depend on what happens when drops and/or bubbles collide with each other, or with the surfaces of other materials. Examples include inkjet printing, agricultural spraying, spray coating of paints, pharmaceutical formulation, stability of cosmetics and foodstuffs, formation of froths and foams, and flow of bubbly liquids. To control these processes, we need to understand how and why drops sometimes do and sometimes do not coalesce with each ....A new angle on the coalescence of drops. Many processes depend on what happens when drops and/or bubbles collide with each other, or with the surfaces of other materials. Examples include inkjet printing, agricultural spraying, spray coating of paints, pharmaceutical formulation, stability of cosmetics and foodstuffs, formation of froths and foams, and flow of bubbly liquids. To control these processes, we need to understand how and why drops sometimes do and sometimes do not coalesce with each other or adhere to surfaces. The knowledge gained in this project will enable improvements to be made in the efficiency of processes such as those listed above.Read moreRead less
Complex Multiscale Systems: Modeling, Analysis and Scientific Computation. This project aims to develop and implement a systematic approach, both analytic and computational, to extract compact, accurate, system level models of complex physical and engineering systems. The wide ranging methodology is to construct computationally efficient "wrappers" around fine scale, microscopic, detailed descriptions of dynamical systems (particle or molecular simulation, or partial differential equations or la ....Complex Multiscale Systems: Modeling, Analysis and Scientific Computation. This project aims to develop and implement a systematic approach, both analytic and computational, to extract compact, accurate, system level models of complex physical and engineering systems. The wide ranging methodology is to construct computationally efficient "wrappers" around fine scale, microscopic, detailed descriptions of dynamical systems (particle or molecular simulation, or partial differential equations or lattice equations). Comprehensively accounting for multiscale interactions between subgrid processes among macroscale variations ensures stability and accuracy. Based on dynamical systems theory and analysis, this approach is expected to empower systematic analysis and understanding for optimal macroscopic simulation for forthcoming exascale computing.Read moreRead less