Hydrodynamic characteristics of double heave plates: A combined experimental and numerical investigation

This study presents a comprehensive investigation into the hydrodynamic characteristics of double heave plates, combining forced oscillation experiments with numerical simulations. The numerical framework is validated against experimental measurements regarding added mass, damping, and vorticity field. The hydrodynamic performance is found to be governed by the plate spacing ratio L / D p ( L is the spacing, D p is the plate diameter), the Keulegan–Carpenter (KC) number, and the non-dimensional oscillation frequency ( β ). In contrast with previous studies, the presented results reveal that the introduction of a second plate may not guarantee enhanced added mass or damping. Indeed, detailed flow analysis reveals that at high β ( β > 1.5 × 1 0 5 ), motion phase lag of the entrapped water between the plate spacing leads to a significant drop in added mass. Moreover, insufficient spacing ( L / D p < 0.25 ) restricts vortex shedding, limiting damping enhancement. Based on the systematic analysis of geometric and oscillation parameters, this study identifies critical thresholds for spacing and plate arrangement to ensure hydrodynamic efficiency in engineering applications.