Recent research indicates that microplastics – plastic pieces measuring 5 mm or smaller -- are now ubiquitous in the environment, having been found in lakes, rivers, and even on ocean floors. Not only may they themselves pose a health risk if consumed, microplastics may act as a vector and promote the spread of other harmful substances in the environment that may otherwise be immobile.
Density-driven flows – or gravity currents -- are believed to play an important role in the horizontal transport of plastics over long distances. Microplastics originating inland may be carried into the sea by river discharge along the water surface or by underwater turbidity currents along the bed. At a global scale, thermohaline circulation may transport microplastics from one part of the world to another. While density-driven flows have been studied for decades, microplastic-laden flows have received relatively little attention until recently. The aim of this project is to improve our understanding of the fate and transport of microplastics in density-driven flows as a function of their size, shape, concentration, chemical composition, and density. Other variables of interest include those that directly affect the propagation of the flow and the turbulence intensity within it, such as the density gradient that drives the flow, the local seafloor topography (e.g., bed slope, vertical and lateral confinement) and, in the case of turbidity currents, the concentration, geometry, and density of the suspended solids.
The successful candidate will generate microplastic-laden density-driven flows as a lock exchange in pipes at different inclines and measure the turbulent velocity field and density distribution using particle image velocimetry and laser-induced fluorescence, respectively (e.g., Tanino et al 2012). The distribution of microplastics in such flows and their evolution will be determined by sampling the water at selected locations as the flow propagates. Using your data as a guide, you will develop predictive models for the propagation speed, interface profile, microplastic distribution, and flow regimes as a function of the experimental variables of your choice.
The primary experiments will be performed in the Aberdeen Tilting Lock Exchange Facility (ATLEF) housed in the Aberdeen Fluid Mechanics Laboratory. The successful candidate will interact regularly with members of the Fluid Mechanics Research Group in the School of Engineering: https://www.abdn.ac.uk/engineering/research/environmental-industrial-fluid-mechanics-122.php . Members of the Group use different combinations of laboratory experiments, field measurements, numerical simulations, and theoretical analysis to study physical processes associated with a wide range of applications, including groundwater remediation, geological CO2 storage, and coastal erosion.
Selection will be made on the basis of academic merit. The successful candidate should have, or expect to obtain, a UK Honours degree at 2.1 or above (or equivalent) in engineering or physical science discipline.
Previous laboratory experience and familiarity with MATLAB are essential. Experience in programming and image processing will be an advantage.
Formal applications can be completed online: https://www.abdn.ac.uk/pgap/login.php
• Apply for Degree of Doctor of Philosophy in Engineering
• State name of the lead supervisor as the Name of Proposed Supervisor
• State ‘Self-funded’ as Intended Source of Funding
• State the exact project title on the application form
When applying please ensure all required documents are attached:
• All degree certificates and transcripts (Undergraduate AND Postgraduate MSc-officially translated into English where necessary)
• Detailed CV, Personal Statement/Motivation Letter and Intended source of funding
Informal inquiries can be made to Dr Y Tanino (email@example.com) with a copy of your curriculum vitae and cover letter. All general enquiries should be directed to the Postgraduate Research School (firstname.lastname@example.org)