Peak Force Measurements on a Cylindrical Buoy With Limited Elastic Mooring

This paper investigates the line force of a moored floating buoy. The experiment was the first experiment made at the Swedish wave energy research site located close to Lysekil on the Swedish west coast. The Lysekil project is run by the Swedish Centre for Renewable Electric Energy Conversion at Uppsala University (Uppsala, Sweden). The experimental setup consists of a cylindrical buoy, with a diameter of 3 m and a height of 0.8 m. The buoy is moored with a line connected to a set of springs in parallel with a rope. The rope in parallel with the springs represents the limited stroke length of a linear-generator-type wave energy converter. The measurement system consists of a force transducer between the buoy and the rope, a three-axis accelerometer inside the buoy, and a remote data logger operated through the Global System for Mobile Communications (GSM) network. The peak forces related to the significant wave height showed a trend of 33 kN/m. Trends were also calculated in 10-kN bins. The data could be used in fatigue simulations of similar devices. The result was very important to set the mechanical design parameters of the first wave energy converter that was deployed at the Lysekil Research Site in March 2006.