Jacob, Sal, Hassan, and Gordon recently published the “Free-Decay Heave Motion of a Spherical Buoy” in Fluids. The buoy response was explored using experimental measurements and complementary numerical simulations. The experiments were performed using MTU Wave’s Qualisys motion-capture system and wave gauges. The simulations included three sets of calculations with varying levels of sophistication. In one set, the volume-of-fluid (VOF) method was used to solve the incompressible, two-phase, Navier–Stokes equations on an overset grid, whereas the calculations. The other sets were based on Cummins and mass-spring-damper models that are both rooted in the linear potential flow theory. Excellent agreements were observed between the experimental data and the results of VOF simulations. Although less accurate, the predictions of the two reduced-order models were found to be quite credible, too.
