Structure Formation Through Coriolis Effects in Rotating Fluid Flows 1=Engineering 2=Fluid Dynamics and Aerodynamics

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Large-scale geophysical flows in the atmosphere and the oceans, as well as flows in rotating machinery, are subject to unique effects arising from the action of the Coriolis force on the flowing liquid. Coriolis forces, due to background system rotation, result in many flow phenomena that are often highly counter intuitive to anyone not familiar with the theory of rotating fluids. Examples include the Taylor-Proudman theorem, Taylor columns, two-dimensional turbulence with its surprising inverse energy cascade where order develops out of turbulent disorder, flow along isobars instead of perpendicular to these and inertial waves. Theoretical formulations exist that predict aspects of these phenomena. However, in many cases the physical mechanism that does facilitate, for instance, structure formation out of disorder and other phenomena, are still a matter of intense debate. Mr Booth will conduct an experimental study using the large-scale tank on our rotating-turntable facility (height 6 metres, diameter 1.5 metre) and study effects such as the formation of Taylor columns and related phenomena using state-of-the-art modern measurement technologies, e.g. Particle Image Velocimetry (PIV). In particular, he will study, for instance, Coriolis effects on the flow dynamics of jets and puffs. These represent examples of two generic flow structures encountered in the natural environment and in applied engineering contexts. The goal of the research is to shed light on the underlying physical process governing the flow dynamics of these structures when modified by Coriolis effects. Our unique laboratory facility at the School of Engineering enables experiments that are currently not possible elsewhere. Depending on the progress of the experimental part of the study, there is scope to perform concurrent computational simulations of some of the aspects investigated. As part of the project, we moreover plan to work in close collaboration with two of the leading theoreticians in the subject area of rotating flows (Prof. Peter A Davidson, University of Cambridge, Department of Engineering and Prof. Alban Potherat, Coventry University, Faculty Research Centre in Fluid and Complex Systems).