A Revisit of Parametrizing Energy Dissipation Caused by Vortex Shedding at Thin-Plate Edges in Potential-Flow Models

Vortex-induced energy dissipation is critical, yet its influence is frequently neglected in potential-flow analysis of wave interaction with thin-walled structures. This study revisits the parametrization of vortex-induced energy dissipation in potential-flow analysis, particularly for wave interaction with vertical, surface-piercing plates. The parametrization is derived by conceptually appending a short perforated region to the vortex-shedding edge of the plate. The underlying physical principle relies on the similarity between vortex shedding from a sharp edge and from an orifice. Two parameters are identified as important: the length of the perforated region and the quadratic loss coefficient associated with the pressure change. For practical applications, the value of the quadratic loss coefficient that is invariant of wave conditions is recommended for a given optimal length of the perforated region. The parametrization is validated using published results for a single plate, and its robustness is further demonstrated through applications involving two surface-piercing vertical plates with varying spacings. The findings of this study can find applications in using potential-flow theory to model plate-type wave breakwaters and wave interaction with thin-walled oscillating water column devices.