资源环境科技发展态势分析平台

Wake vortices in tidally modulated currents past a conical hill in a stratified fluid are investigated using large‐eddy‐simulation. The vortex shedding frequency is altered from its natural steady‐current value leading to synchronization of wake vortices with the tide. The relative frequency (f*), defined as the ratio of natural shedding frequency (f _s,c ) in a current without tides to the tidal frequency (f _t ), is varied to expose different regimes of tidal synchronization. When f* increases and approaches 0.25, vortex shedding at the body changes from a classical asymmetric Kármán vortex street. The wake evolves downstream to restore the Kármán vortex‐street asymmetry but the discrete spectral peak, associated with wake vortices, is found to differ from both f _t and f _s,c , a novel result. The spectral peak occurs at the first subharmonic of the tidal frequency when 0.5 ≤ f* < 1 and at the second subharmonic when 0.25 ≤ f* < 0.5.