Dr James Cooper
Postdoctoral Research Associate
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Room number: | |
| Telephone (internal): | 27989 | |
| Telephone (UK): | 0114 222 7989 | |
| Telephone (International): | +44 114 222 7989 | |
| Email: | J.Cooper@Sheffield.ac.uk |
James Cooper has a BSc in Geography (2002) from the University of Sheffield, where he also obtained his PhD in Civil Engineering (2006) on 'Spatially-induced Momentum Exchange over Water-Worked Gravel Beds', in which his work examined flow spatial variability and its significance for momentum transfer in gravel-bed rivers. From 2005 he held an ARCO Research Fellowship in Environmental Fluid Dynamics at the University of Hull, and in 2009 took up a lectureship in Civil and Environmental Engineering at the University of Bradford. James moved back to full-time research in August 2010 to work as a PDRA on a NERC-funded project on overland flow dynamics and soil erosion.
Research Interests
His interests lie in understanding the complex interaction between turbulent flows and water-worked sediment beds. This has included: (1) describing the spatio-temporal characteristics of turbulent flow; (2) examining spatial stress patterns; (3) measuring and parameterising hydraulic resistance; and (4) characterising bed surface topography and the subsurface properties of water-worked sediment beds. A key approach has been to use laboratory flume channels to investigate the key variables which effect the dynamics of the flow field through the use of advanced laser and acoustic flow measurement techniques. More recent interests have developed into examining how these dynamics influence sediment stability. His work until now has been within the area of river hydraulics, and his current role will see the experience he has gained used within the field of overland flow dynamics and soil erosion.
James has particular expertise in the use of Particle Image Velocimetry, having made detailed measurements over both static and mobile sediment beds in a number of studies. He has coupled this work with the utilisation of double-averaging methodology (DAM) to examine the relative importance of different flow mechanisms in transferring momentum over water-worked sediment beds. The use of PIV and DAM remain key elements to his work.
Current Research
Dynamics of Runoff and Erosion Modelling (DRAEM)
I am working as a PDRA on a NERC funded project which is examining the dynamics of overland flow and soil erosion. Laboratory experiments are being performed using high-speed, high-resolution imaging and PIV techniques which can simultaneously track sediment particles and measure the spatio-temporal properties of the flow. This will enable the characterisation of the dynamics of the different components of the detachment, transport and deposition processes in shallow overland flows. These data will be used to develop submodels within an existing soil-erosion model (MAHLERAN).
More information on DRAEM
High Resolution, Non-intrusive Shear Stress Measurement in Fluvial Environments
I am co-investigator on a NERC funded project developing a novel image-based laboratory system for measuring boundary shear stress. We are developing shear stress sensitive liquid crystal coatings that are capable of being attached to natural sediments. The new coatings make it is possible to measure directly, in-situ, and at high spatial and temporal scales, the shear stress imposed on sediment deposits by turbulent water flows. The results from this new technique will be used to enhance our understanding of sediment transport and drag processes by use of an existing grain-scale numerical model.
More information on my Shear Stress Measurement research
Details of other recent projects can be found on the right hand side of this page under "Further Details".
Key Publications
- Mao, L., Cooper, J.R. and Frostick, L.E. (2011, in press). Grain size and topographical differences between static and mobile armour layers. Earth Surface Processes and Landforms.
doi:10.1002/esp.2156 - Cooper, J.R. and Tait, S.J. (2010). Spatially representative velocity measurement over water-worked gravel beds. Water Resources Research, 46, W11599.
doi:10.1029/2009WR008465 - Cooper, J.R. and Tait, S.J. (2010). Examining the physical components of boundary shear stress for water-worked gravel deposits. Earth Surface Processes and Landforms, 35(10), 1240-1246.
doi:10.1002/esp.2020 - Cooper, J.R. and Tait, S.J. (2009). Water-worked gravel beds in laboratory flumes: a natural analogue? Earth Surface Processes and Landforms, 34(3), 384–397.
doi:10.1002/esp.1743 - Cooper, J.R. and Tait, S.J. (2008). The spatial organisation of time-averaged velocity and its relationship with the bed surface topography of water-worked gravel beds. Acta Geophysica, 56(3), 614-642.
doi:10.2478/s11600-008-0023-0 - Cooper, J.R., Tait, S.J. and Horoshenkov, K.V. (2006). Determining the hydraulic resistance of gravel-bed rivers from the dynamics of their water surfaces. Earth Surface Processes and Landforms, 31(14), 1839-1848.
doi:10.1002/esp.1447