Microscale Mechanisms: The Influence of Particle Geometry on Aerodynamic Resuspension

About the Project

Applications are invited for a 4 year PhD studentship starting in Autumn 2026 as part of the EPSRC CDT in Aerosol Science

Project Overview

Road dust resuspension by passing vehicles is the dominant source of particulate air pollution in urban environments, exceeding contributions from brake wear, tyre wear, and vehicle exhaust combined. Yet despite their importance, the fundamental mechanisms controlling particle resuspension remain poorly understood, particularly for non-spherical particles with complex geometries.

This PhD project will systematically investigate how particle shape influences the aerodynamic forces that cause resuspension through innovative millimetre-scale experiments in wind tunnels and water flumes.

Research Approach

You will develop a novel electromagnetic measurement system that holds test particles in place against flowing fluid. By measuring the current at the moment of particle lift-off, you will directly quantify the critical resuspension force for particles of different shapes—a significant methodological advance impossible at microscopic scales.

Systematic experiments will investigate disc- and dome-shaped particles with varying aspect ratios, flow speeds, and turbulence levels. Particle Image Velocimetry (PIV) will capture flow fields immediately before resuspension, while you develop physics-based mathematical models to explain and predict particle behaviour.

Timeline

Year 1: Design and build the electromagnetic force measurement apparatus

Years 2-3: Execute systematic shape experiments and develop mathematical models; introduce controlled turbulence effects

Possible extensions: Particle-particle interactions and surface roughness effects

Impact

Your findings will directly inform urban air quality understanding and provide crucial data for computational models of particulate transport, with applications spanning environmental science, industrial processes, and pharmaceutical powder handling.

Candidate Profile

We seek motivated candidates with strong backgrounds in engineering, physics, applied mathematics, or related disciplines, with enthusiasm for experimental research and apparatus development. While prior experience with these specific experimental techniques is not essential, candidates with a background in experimental fluid mechanics will be at an advantage.

Dr Megan Davies Wykes (msd38@cam.ac.uk) welcomes informal enquiries from interested candidates.

About the Centre for Doctoral training in Aerosol Science

Aerosol science is crucial to disciplines as broad ranging as transmission of disease, drug delivery to the lungs, climate change, energy and combustion science, novel materials, and consumer and agricultural products.

An aerosol is any collection of particles dispersed in a gas. The CDT brings together a multi-disciplinary team of 80 post-graduate students and academics from 8 UK universities spanning the physical, environmental and health sciences, and engineering. Our aim is to tackle the global challenges in which aerosol science is key.

Further details are available from our website: https://www.aerosol-cdt.ac.uk/

Doctoral Training in Aerosol Science

During your doctorate, you will learn to research in diverse multidisciplinary teams, gain an advanced understanding of the core physical science of aerosols, and collaborate with industrial and public sector partners, equipping you to undertake ground-breaking research in aerosol science.

During the first 7 months of your PhD, you will join the CDT cohort based at the University of Bristol. Core training in aerosol science, research methods, professionalism and translation will be delivered by Team Based Learning. You will then undertake a short research project at your home or partner institution before starting your PhD research. You will gain experience outside academia in a placement with an industrial/public sector partner in Year 2 or 3.

More Information and How to Apply

Candidates who aspire to work in a multidisciplinary field, and hold or will achieve a minimum of an upper second-class undergraduate degree in any of these areas are encouraged to apply: chemistry, physics, biological sciences, life and medical sciences, mathematics and computer science, chemical and mechanical engineering, pharmaceutical and environmental sciences.

Visit our website: https://www.aerosol-cdt.ac.uk/ Contact us: aerosol-science@bristol.ac.uk

Funding Notes

This project is funded as part of the EPSRC CDT in Aerosol Science. Successful candidates meeting the funding criteria will receive a studentship covering tuition fees, research and training support grant, plus a stipend to cover your living expenses while you train, paid at the standard UKRI rate.