Pollution in Nearshore Waters
Coastal recreational waters should comply with the appropriate water quality standards. In Europe these standards are defined by the new EU Bathing Waters Directive (2006/7/EC). Industrial and sewage treatment works often discharge their effluent into estuarine or coastal waters. Increased awareness by both regulatory bodies and the general public has made it vital to assess the effect of pollutants within coastal waters. In numerical models of the coastal region, the flows are usually depth averaged two dimensional simulations and tidal variations are used to predict velocities. The physical dispersal of plumes from waste disposal sites in the coastal zone is then simulated using the predicted velocity distributions and an estimated mixing coefficient.
At present these models are limited in their predictive capability due to a lack of detailed understanding of the hydrodynamic processes associated with bed shear stress, turbulence and mean velocity field, resulting in an inability to distinguish between the individual contribution of wave activity and current action on the mixing processes. This proposed research will extend current research and knowledge using novel experimental techniques to elucidate physical processes and provide descriptions of the key mass exchange processes and turbulent wave velocity fields.
The provision of the new 2D wave flume facility at Warwick, together with the specialist measurement available will provide the applicants with a unique opportunity to investigate the 'finer' mixing mechanisms responsible in the nearshore region, particular emphasis would be placed on measurement of the hydrodynamics (such as the vertical variation in velocity and wave generated turbulence), which would further refine the understanding of mechanisms responsible for the mixing. The use of non-intrusive measurement systems such as a laser light sheet provides the opportunity to investigate the hydrodynamics using PIV, and the diffusion/dispersion processes using PLIF (Planar Laser Induced Fluorescence).
Contamination into Beaches
The overall aims of this proposed research are to improve the understanding and descriptions of key coastal processes in the nearshore region, with particular emphasis on those exchange processes influencing contamination into beaches. The applicants previous experimental investigations showed that the depth-varying forward transport under waves was a significant contributory factor to the on-off shore dispersion coefficient (Pearson et al. 2002, 2009) within the water column. In the case of contamination into beach material it is by no means clear how the mass transport and associated bed exchange mechanisms will be developed under the influence of wave activity. This project will utilise the research grade 2D wave flume in the School of Engineering at the University of Warwick utilising the vast array of scientific measurement equipment already available at Warwick. New knowledge of hydrodynamic and exchange processes will be obtained through interpretation of unique velocity and tracer measurements.
For more information please contact Dr Jonathan Pearson.
Note: Should your application for admission be accepted you should be aware that this does not constitute an offer of financial support. Please refer to the scholarships & funding pages.