Partrac, the marine data acquisition experts, has completed the first turbulence survey for the Carbon Trust-managed Turbulence in Marine Environments (TiME) project.
The survey was undertaken in the Sound of Islay and was designed by Partrac with project partners, Ocean Array Systems, ABPmer, and ITPower. Innovative turbulence measurement instruments were provided by Rockland Scientific International (RSI) in Canada.
The survey included four standard ADCP units, and one advanced five beam Nortek AD2CP unit, each positioned on the sea bed. Three of the locations were at positions where tidal turbines will be installed. A RSI ‘Nemo’ turbulence mooring was also deployed so that turbulence data could be measured at turbine hub-height. The measurements were taken over a 28-day period during April and May. In addition, a VMP-250 (vertical micro-profiler) was used over two days to gather around 50 profiles of turbulence in the water column. All instruments were deployed to meet industry best practice with the ADCP pitch and roll parameters at less than 5 degrees for the duration of the monitoring period. Data was recorded at a high frequency, which is required to understand turbulence, and resulted in over 700,000 data records per instrument. All equipment was retrieved successfully.
Peter Wilson, a Director and co-owner at Partrac , said “This is a very exciting project. This is the first time that such a large survey has been designed to specifically measure turbulence using a range of acoustic and non-acoustic measurement techniques. To get data at hub height is a first in such tidal currents and to be able to map turbulence across a development site will be invaluable to developers.”
The data collected has now been post-processed by Partrac and RSI and is being provided to the partners for the next stage in the project. ABPmer is undertaking resource characterisation, Ocean Array Systems is providing turbulence characterisation and hydrodynamic analyses, and ITPower is contributing their knowledge of engineering design and device performance.
The next survey deployment is planned for the Inner Sound of the Pentland Firth at the end of the summer 2014.