Entrainment and Mixing in Turbulent Negatively Buoyant Jets and Fountains. The project intends to develop tools to accurate predict fountain flows. Volcanic eruptions, building ventilation and brine discharge from desalination plants are all examples of turbulent fountains and negatively buoyant jets. The project aims to conduct an investigation into the turbulent structure of fountains and negatively buoyant jets using numerical simulation and laboratory experiments, and to assess the accuracy ....Entrainment and Mixing in Turbulent Negatively Buoyant Jets and Fountains. The project intends to develop tools to accurate predict fountain flows. Volcanic eruptions, building ventilation and brine discharge from desalination plants are all examples of turbulent fountains and negatively buoyant jets. The project aims to conduct an investigation into the turbulent structure of fountains and negatively buoyant jets using numerical simulation and laboratory experiments, and to assess the accuracy of the commonly used integral models and test the effect of the use of more accurate entrainment relations. This may have a range of applications – enabling better prediction of environmental impacts, reduction of the adverse effects of the discharge of pollutants, and reduction in energy consumption in building ventilation and other industrial applications.Read moreRead less
Thermal stratification, overturning and mixing in riverine environments. Thermal stratification is common in Australia's rivers due to our hot, drought-prone climate and high human demands relative to available supply, which has led to a significant reduction in flows relative to natural levels. Thermal stratification inhibits mixing, creating stagnant conditions characterised by low oxygen levels and increased concentrations of contaminants, leading to algal blooms, fish kills and systemic dama ....Thermal stratification, overturning and mixing in riverine environments. Thermal stratification is common in Australia's rivers due to our hot, drought-prone climate and high human demands relative to available supply, which has led to a significant reduction in flows relative to natural levels. Thermal stratification inhibits mixing, creating stagnant conditions characterised by low oxygen levels and increased concentrations of contaminants, leading to algal blooms, fish kills and systemic damage to ecosystems. The aim of this project is to develop predictive models for the effects of physical processes such as night-time cooling, wind, turbulence and currents on riverine thermal stratification. This is expected to enable a more accurate determination of the flow rates required to maintain the health of our river systems.Read moreRead less
Studies of turbulence and coherent structures in quasi two-dimensional plasmas and fluids. One of the most celebrated but least understood complex systems in nature is turbulent flow. This cross-disciplinary project aims to contribute to basic scientific knowledge of a class of turbulent flows, known as quasi two-dimensional fluids, that typically exhibit self-organizing properties, stable sheared flow, and relatively weak dissipation. The significance lies in the proposed testing, by modelling ....Studies of turbulence and coherent structures in quasi two-dimensional plasmas and fluids. One of the most celebrated but least understood complex systems in nature is turbulent flow. This cross-disciplinary project aims to contribute to basic scientific knowledge of a class of turbulent flows, known as quasi two-dimensional fluids, that typically exhibit self-organizing properties, stable sheared flow, and relatively weak dissipation. The significance lies in the proposed testing, by modelling and simulation studies, of the well-grounded hypothesis that suppression of turbulence by sheared flow is a universal phenomenon in such fluids, and that it can be exploited to control transport of fluid constituents. Applications of this new knowledge will be developed.Read moreRead less
Structural transitions in turbulent fluids and plasma through self-organization. Studies into structural transitions in turbulent systems will greatly benefit Australia through its contributions to the science of complex systems, in the areas of self-organization and turbulence control. Applications range from understanding the formation of the Earth's atmospheric spectrum to generation of transport barriers in magnetically confined plasma, as well as development of novel methods of turbulence c ....Structural transitions in turbulent fluids and plasma through self-organization. Studies into structural transitions in turbulent systems will greatly benefit Australia through its contributions to the science of complex systems, in the areas of self-organization and turbulence control. Applications range from understanding the formation of the Earth's atmospheric spectrum to generation of transport barriers in magnetically confined plasma, as well as development of novel methods of turbulence control in engineering. Recent discoveries by the authors open a window of opportunity for a breakthrough in this fundamental field of modern science. The project is based on several national and international collaborations. Australian postgraduate and research training is an integral part of the project.Read moreRead less
A Laboratory Study of Ocean-Atmosphere Coupling in the Antarctic Circumpolar Wave. A laboratory model of the southern hemisphere mid-latitude ocean-atmosphere system will be used to investigate the dynamics of ocean-atmosphere coupling contributing to the Antarctic Circumpolar Wave (ACW). The ACW is a recently discovered multi-year climate oscillation which has considerable effect on Australian and New Zealand precipitation. This will be the first laboratory model to include global scale ocean-a ....A Laboratory Study of Ocean-Atmosphere Coupling in the Antarctic Circumpolar Wave. A laboratory model of the southern hemisphere mid-latitude ocean-atmosphere system will be used to investigate the dynamics of ocean-atmosphere coupling contributing to the Antarctic Circumpolar Wave (ACW). The ACW is a recently discovered multi-year climate oscillation which has considerable effect on Australian and New Zealand precipitation. This will be the first laboratory model to include global scale ocean-atmosphere processes, and will be used to test proposed mechanisms for the driving of the climate oscillation that is attributed to the ACW. The project will provide knowledge required for improved computational modelling and climate predictions.
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Nonlinear optics of soft matter. This project will develop new strategies for the use and control of soft-matter systems by exploiting nonlinear interactions with light, and therefore falls into the Designated Research Priority 3: Frontier Technologies for Building and Transforming Australian Industries - Breakthrough Science. With soft matter research being increasingly important for applications within industry and medicine, the emergence of new technology for control of nanoparticles could pr ....Nonlinear optics of soft matter. This project will develop new strategies for the use and control of soft-matter systems by exploiting nonlinear interactions with light, and therefore falls into the Designated Research Priority 3: Frontier Technologies for Building and Transforming Australian Industries - Breakthrough Science. With soft matter research being increasingly important for applications within industry and medicine, the emergence of new technology for control of nanoparticles could provide significant benefits for the scientific community as well as Australian companies.
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Relationship between subduction zone geometry, trench kinematics and great subduction earthquakes. The devastating Boxing Day 2004 earthquake near Sumatra and the four other largest earthquakes in recorded history all occurred along subduction zones. This research will compare the geodynamic setting of these subduction zones with those surrounding the Australian continent and assess whether the Australian subduction zones are capable of producing great earthquakes and tsunamis that might pose a ....Relationship between subduction zone geometry, trench kinematics and great subduction earthquakes. The devastating Boxing Day 2004 earthquake near Sumatra and the four other largest earthquakes in recorded history all occurred along subduction zones. This research will compare the geodynamic setting of these subduction zones with those surrounding the Australian continent and assess whether the Australian subduction zones are capable of producing great earthquakes and tsunamis that might pose a risk for the east and northwest coast of Australia. Also, Eastern Australia is a composite of fossil arcs rich in ore deposits and the Tasman Sea region is composed of basins that host hydrocarbons, all of which formed by subduction processes. The proposed research will thus improve the basis for mineral and hydrocarbon exploration.Read moreRead less
Rarefied hypervelocity separated flow in the transitional to continuum regimes. The transition regime for low-density flows is a no-man's-land between free-molecular and continuum flow, where the flow behaves differently to the assumptions typically used for modelling either flow type. Bird's direct Simulation Monte Carlo (DSMC) method is typically thought to be the best way of modelling these flows, but has not produced excellent agreement with previous experiments on low-density separated flow ....Rarefied hypervelocity separated flow in the transitional to continuum regimes. The transition regime for low-density flows is a no-man's-land between free-molecular and continuum flow, where the flow behaves differently to the assumptions typically used for modelling either flow type. Bird's direct Simulation Monte Carlo (DSMC) method is typically thought to be the best way of modelling these flows, but has not produced excellent agreement with previous experiments on low-density separated flows, due to computational limitations and lack of knowledge of the flow's internal energy. This proposal is a blind test of the best current DSMC codes against our experiments and a hypersonic continuum code, with the full internal energy state of the flow experimentally quantified for the first time.Read moreRead less
Nanorheology: Hydrodynamic Slip in Newtonian Fluids. Understanding fluid flow across a surface is essential to a great number of technologies. For over one hundred years it has been assumed that the layer of fluid adjacent to the solid moves with the solid, this is known as the no-slip boundary condition. Recently direct force balance measurements of aqueous Newtonian solutions have indicated the presence of boundary slip. Using a newly developed nanorheology technique we will systematically inv ....Nanorheology: Hydrodynamic Slip in Newtonian Fluids. Understanding fluid flow across a surface is essential to a great number of technologies. For over one hundred years it has been assumed that the layer of fluid adjacent to the solid moves with the solid, this is known as the no-slip boundary condition. Recently direct force balance measurements of aqueous Newtonian solutions have indicated the presence of boundary slip. Using a newly developed nanorheology technique we will systematically investigate the conditions that control boundary slip. This information will be used to quantify, model and control boundary slip, progressing the fields of microfluidics, particle deposition, and colloid stability.Read moreRead less
Mixing and dissipation in the ocean: Processes for the next generation of climate models. The circulation of the oceans is a crucial factor in governing the variability and long-term change in the earth's climate. A major weakness in current ocean and climate models is a lack of knowledge of energy flow within the ocean. This project will examine the nature and role of eddy interactions with the ocean boundaries, which is a critical question for future development of more accurate high-resolutio ....Mixing and dissipation in the ocean: Processes for the next generation of climate models. The circulation of the oceans is a crucial factor in governing the variability and long-term change in the earth's climate. A major weakness in current ocean and climate models is a lack of knowledge of energy flow within the ocean. This project will examine the nature and role of eddy interactions with the ocean boundaries, which is a critical question for future development of more accurate high-resolution ocean models and improved climate predictions.Read moreRead less