Turbulence in density currents

Currents, driven by a density difference from the ambient surroundings, are an important class of geophysical flow, pertinent to atmospheric, terrestrial, deep marine and inner earth environments, yet their mechanics remain poorly understood. Critical to understanding such ‘density currents’ is the turbulent motion of the flow, which dictates the distribution of flow density via turbulent diffusion and ambient fluid entrainment. This studentship will investigate an often neglected, yet vital, mechanism by which turbulence effects density current flow dynamics – large-scale coherent vorticity. Experimental and numerical based research will address how such processes scale with flow size.

All previous experimental studies have only acquired two-dimensional low-resolution data. This studentship will deliver a step-change in observational based understanding of flow dynamics through the use of revolutionary ultrasonic and optical techniques to collect high-resolution planar and full 3D flow velocity data. Complementing this numerical model development will enable study of scaling of turbulence in density currents, linking the laboratory to real-world flows. The combined program will enable the development of idealised theoretical models enhancing our understanding of density current dynamics, providing a valuable insight into the controls of this important class of geophysical flow.