Real-world performance with accurate current measurement
UK-based Tidal Generation Limited turned to Nortek for help with current measurement analysis when they were developing an impeller tidal turbine to produce electrical energy from tidal currents.
Tidal Generation contacted Nortek when they wanted to analyze the relationship between incoming currents and produced energy, to understand the effect of waves, and, possibly, in the future to control the pitch of the turbine blades.
The company needed to measure the wave height right in front of their newly developed impeller tidal turbine, while detailing the current profile 35 m in front of the turbine. Furthermore, they did not want anything to be mounted on the seafloor, and they wanted data to be available online.
The ingenious solution designed at Nortek used the AWAC sensor’s electronics, but not the standard mechanical design. Instead, a peculiar-looking transducer head combined with some extra data processing took the measurements from two beams tilted at 73° from the vertical to generate the full current profile. The vertical beam measured the distance to the surface and this data was used to calculate the wave height using Nortek’s Acoustic Surface Tracking (AST) algorithms.