The, statistically-Unsteady, Next generation Sediment Transport model for Environmental flows

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The transport of sediment by environmental flows shapes the world around us. Our ability to predict sediment transport is therefore key to a range of disciplines and sectors, and is critical to water, energy and food security. For example, accurate sediment transport prediction is key in the management of natural environments, screening and mitigation of geohazard risks, design and operation of offshore windfarms and exploitation of natural resources. Research in these areas directly addresses key UK and global challenges, including clean and secure energy, geohazard resilience and ecosystem management in changing natural and societal environments. Despite its clear importance, state-of-the-art predictive sediment transport models are still based on a century-old paradigm, recognised as flawed, and of limited applicability, even when first proposed. Therefore, our current ability to predict sediment transport in real-world environments is limited. Predicting sediment transport is dependent on understanding how much material is kept aloft, suspended in flowing water. Current models of sediment suspension are inaccurate, dependent on a model of mixing of slowly-settling particles, over vanishingly small length-scales, by random fluid motion (turbulence). However, recognised even when first developed, these models are based on flawed assumptions of the role and scale of turbulence in real-world flows. Moreover, recent research spanning earth sciences and mathematics highlights that chaotic, turbulent fluid motion is not always entirely random. Under many conditions coherent structures can develop, and in atmospheric flows it has been shown that coherent structures result in self-organisation. The emergence of self-organisation from chaos is fascinating, operating against preconceived notions of increasing entropy, and hinting at higher levels of physical complexity than is currently understood.Building on my multidisciplinary background, covering mathematics and earth sciences, and collaborating with international experts in academia and industry, I will undertake the first study of the development of coherent structures and self-organisation in sediment-laden environmental flows. To achieve this, this Fellowship aims to integrate recent developments in theoretical and empirical research of turbulent flows - with the objective of making a step-change in the way in which sediment suspensions are modelled. Such integrated research is not only crucial, but it is also timely, only now possible due to scientific and technological advances made in the past decade. Critical to this is University of Hull commitment to directly support development of a globally unique stratified flow facility for studying suspended sediment transport. Moreover, I will advance the Fellowship research to study real-world systems, where the composition of sediment suspensions vary, enabling impact across the applied sciences. Working with international collaborators, I will apply these sediment transport models to help constrain the magnitude and frequency of geohazard risk posed by environmental flows.Synergistic to the Fellowship 2xPhDs , funded by the University of Hull, will facilitate impact as students will apply Fellowship research to address challenges in energy security, geohazard resilience and ecosystem management. Direct engagement with academic, industrial and government collaborators will maximise impact throughout the Fellowship. Collaboration will enable me to naturally develop a Centre for Environmental Fluid Dynamics at the University of Hull, which I will use to develop and broaden Fellowship research studying the impact of the built environment, e.g. offshore windfarms, on environmental flows and the mechanics of high-concentration flows. Thus, this Fellowship, and subsequent research, will enable me to address current and future societal challenges in earth surface science as a research leader in environmental fluid dynamics.