Experimental Study of Return Flow Drawn from Harbour Resonators

Abstract

<p>This report describes an experimental investigation into the potential use of return flow from rectangular harbour resonators incorporated into semi-infinite harbour entrances. The mechanism studied includes: the bandwidth of the reduced energy spectrum transmitted into a harbour, the concomitant reflected wave spectra and the energy available for return flow. This report is intended to provide data for the design of on-channel harbour resonators so as to eliminate or reduce the transmission of a selected band of harmful wave frequencies and to maximize the energy of scouring currents so as to prevent the influx and deposition of littoral sediments in harbour entrances. Observations were also made of the potential danger to small vessels provided by the movement of waves into and out of the resonators. The vessels would probably be ejected from the resonator without risk of battering, although the motion locally in the mouth of the resonator will be amplified.</p>