Near-critical free-surface rotating flow over topography

Abstract

Free–surface rotating flow over localized topography is studied in the weakly three–dimensional nonlinear long–wave dispersive limit. The analysis is based on the forced rotating Kadomtsev–Petviashvili (frKP) equation. For small forcing, steady supercritical flow is described analytically. Finite–amplitude topographic effects are described numerically for both supercritical and subcritical flows. The pressure drag on the flow is described as a function of obstacle height, Rossby number and the detuning parameter measuring the difference between the flow speed and that of linear long gravity waves.