05 Jul 2010

HYDRALAB boosts hydraulic laboratories

What started out as Round Table meetings in 1997 has gradually become an integrated series of pan-European research initiatives to coordinate and provide access to large scale experimental facilities.

What started out as Round Table meetings in 1997 has gradually become an integrated series of pan-European research initiatives to coordinate and provide access to large scale experimental facilities. Hydraulic laboratory installations - under the HYDRALAB umbrella - were among some of the first facilities to be supported by this EU initiative. The third stage of this successful programme has now come to an end.

Initially HYDRALAB defined a strategy paper in which the consortium sets out the strategy for the future of large-scale experimental facilities in the general field of hydraulics. It concluded that there was a compelling need for balance in the hydraulic research methodology. Even more, there was a need for synergy between the various research tools available such as physical models, numerical models, theoretical analysis and field experiments.

"Looking back HYDRALAB has been instrumental in escalating experimental work to a higher level and in developing the techniques such as integration of numerical modelling systems, field measurements, experimental laboratory research in special-purpose facilities and theoretical analyses leading to what we now call composite modelling" says Jens Kirkegaard, DHI, who has been active in the HYDRALAB consortium from the first days. "One the objectives with HYDRALAB was also to bring well educated and skilled young researchers from across Europe to the top level of research found in few institutions across Europe and to optimise the use of costly experimental infrastructure. We have certainly achieved this. Here at DHI we have hosted a number of young researchers which have used our experimental facilities" he adds.

One of the recent projects carried out at DHI was done by members of the Warwick team who undertook experimental investigations in the wave-current facility to investigate the pollutant dispersion generated by long shore currents.

The joint study between The University of Warwick and The University of the Aegean, Greece was principally aimed at understanding the fates of pollutants in near shore coastal regions. Project leader Dr Jonathan Pearson commented "This work is essential to improve fundamental understanding of near shore hydrodynamic processes contributing to pollutant mixing. The resulting predictive techniques will be beneficial to consultant engineers, coastal managers, local authorities and government agencies responsible for water quality. Data on the near shore hydrodynamics and dispersion will improve the verification of numerical models, which will allow a better understanding of how wave activity transports pollutants and nutrients".

The research focuses on waves which approach the shore at an oblique angle, resulting in a wave driven long shore current. Regular and random waves are being studied and direct solute tracer measurements allow the on-offshore pollutant transport to be quantified. Laser Doppler Anemometry measurements are also being undertaken, which provide unique turbulence measurements in and around the surf-zone. This data together with the direct tracer measurements will allow validated algorithms to be developed that describe the contributions to pollutant dispersion in the near shore zone produced by combined wave-current processes.

"The Warwick work is just an example of how HYDRALAB has made it possible to get access to such facilities, which otherwise in most cases would be out of bound for universities" says Jens Kirkegaard.

The types of projects undertaken cover a wide range of areas ranging from dikes to wave power converters, as illustrated by some of the projects carried out, i.e.

  • Flowdike: Investigating the effect of wind and current on wave run-up and wave overtopping.
  • Experimental study of the slowly varying wave exciting drift forces on a body of simple geometry
  • Violent wave interactions with a vertical cylinder - applications to offshore wind turbine foundations and "ringing" re-visited.
  • Hydrodynamic performance of the Anaconda wavepower device

Twenty partners from all over Europe participated in the HYDRALAB III consortium.