Decommissioning, Immobilisation and Storage Solutions for Nuclear Waste Inventories (DISTINCTIVE)
Project Funder: EPSRC
Project lead and collaborators: Fairweather (PI), with Imperial College London, Lancaster University, Loughborough University, University College London and the Universities of Birmingham, Bristol, Manchester, Sheffield and Strathclyde
Research Theme: Particulate Flows, Sediments and Rheology
Summary of project
This consortium project addresses nuclear waste and decommissioning, bringing together industry partners and academic researchers from ten leading universities. The research underway covers both fundamental and applied topics in four research themes: AGR, magnox and exotic spent fuels; plutonium oxide and fuel residues; legacy ponds and silo wastes; and structural integrity. Fluid dynamics-related work at the University of Leeds, relevant to legacy ponds and silo wastes, concerns improving our understanding of the behaviour of nuclear waste sludge materials through experimental study and quantitative predictive procedures. This is of benefit to the design of more efficient and safer waste treatment processes. One project focuses on the use of realistic sludge simulants, with a range of particle shapes and sizes, and their flow in pipes. Characterisation of the segregation of the particle materials within these flows is being undertaken using novel ultrasonic approaches. Predictions of these flows are being made using a coupled large eddy simulation/Lagrangian particle tracking technique. The influence of levels of turbulence, and the direction of gravity, on particle agglomeration and settling behaviour, and the shear break-up of particle aggregates, is being explored. Ultimately, our goal is a validated predictive model for complex particle-laden flows in closed pipes.
Predictions of spatial and orientational distribution of needle-like particles deposited on the lower wall of a channel flow
Experimental investigation showing the formation of ripple bed forms of regular period from particle deposition in a particle-laden pipe flow.