EXPERIMENTAL TESTS OF A 1:16TH-SCALE MODEL OF THE SPAR-BUOY OWC IN A LARGE SCALE WAVE FLUME IN REGULAR WAVES

摘要

This paper presents the experimental tests of a 16th-scale model of the Spar-buoy oscillating water column (OWC) carried out at a large scale wave flume. The model is slack-moored to the flume floor by two mooring lines. The turbine effect is replicated using calibrated orifice plates. The device six degree-of-freedom motion, inner free surface displacement and air chamber pressure are measured. The influence of wave height, turbine damping and mass distribution on the system dynamics is analysed for regular waves. An in-house developed numerical time-domain model is used to simulate the motion and power absorption under the same wave conditions as the physical model tests. The formulation considers linear hydrodynamic forces, viscous drag effects and drift forces. The floater is assumed to oscillate in six degrees of freedom and the OWC can move vertically in the tube. The mooring system is simulated using a quasi-static model. The comparison between experiments and numerical simulations shows a good agreement for wave periods outside the zone where parametric resonance in roll and pitch occurs.