We examine the rheology of granular dense suspensions using computer simulations with discreste particles and develop constitutive models for flow of such suspensions.
Mud, slurry, coffee, paints, cements, batteries and many other everyday materials have particles suspended in a liquid. We need to understand the flow behaviour to handle, and process such materials for traditional and innovative applications. Our research seeks to understand the common features of the flow behaviour of different materials using simple particle based simulations. In particular, we focus on dense suspensions where the particles occupy more than 50 % by volume of the solution.
The research focuses on understanding cohesive powder flow in flexible bulk solid containers (buggies and bulk bags) with a view to develop a design methodology for ensuring reliable discharge from these containers. The project involves experimental powder flowability characterisation, finite element analysis of the stresses in flexible containers and pilot scale experiments to study the powder flow field and validate the new design methodology for reliable discharge.
When a load is applied to an assembly of particles and particle breakage occurs, the macroscopic behaviour of the assembly is greatly affected by changes in the micro-scale caused by breakage. In this project particle breakage is studied in 3D using x-ray tomography and simulating the process with the DEM.
This project aims to develop a robust methodology to characterise the grindability of particulate products in milling operations which will in turn provide a step-change in mill fingerprinting and optimisation. This involves developing a “grindability test” to measure the comminution characteristics of the particulates which, when coupled with the computational modelling work to characterise the milling function, will evaluate the milling performance measures including energy utilisation, breakage kernels for scale-up modelling such as population balance model of the mill.
To enlarge the scale of discrete element modelled particulate system from spherical to nonspherical; to increase the computational efficiency of simulating the nonspherical system; to provide more insights of particulate solid mechanics in engineering applications.
The Edinburgh part of the project focues on the multi-physics modelling of particle dynamics and sintering behaviour in selective laser sintering processes. This work is an integrated part of an EPSRC funded project to develop fundamental understanding of particle behavour in additive manufacturing, collaborating with the University of Exeter. This project proposes to investigate the way polymeric powders of different shapes and sizes flow, interact and sinter in the laser sintering process, through modelling and experimental validation. Laser sintering is part of the additive manufacturing technology, known for its benefits in industries where custom made products, lightweight and complex designs are required.
![The shear vane test model built with the DEM software EDEM. [Note: the grey colour represents the vane and consists of two perpendicular blades and the rigid solid particles were generated in fixed boundary];](https://eng.ed.ac.uk/sites/eng.ed.ac.uk/files/styles/medium-2/public/images/research/projects/1.png?itok=JyJoyZkx "The shear vane test model built with the DEM software EDEM. [Note: the grey colour represents the vane and consists of two perpendicular blades and the rigid solid particles were generated in fixed boundary];")
