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Indexed by:Journal Papers

Date of Publication:2015-12-01

Journal:CHINA OCEAN ENGINEERING

Included Journals:SCIE、EI、ISTIC、Scopus

Volume:29

Issue:6

Page Number:917-924

ISSN No.:0890-5487

Key Words:wavemaker; active absorption; IIR digital filter; time delay

Abstract:Physical model tests with highly reflective structures often encounter a problem of multiple reflections between the structures and the wavemaker. This paper presents a piston-type active absorbing wavemaker system which can absorb most of the reflections. Based on the first-order wavemaker theory, a frequency domain absorption transfer function is modeled. Its time realization can be achieved by designing an IIR digital filter, which is used to control the absorbing wavemaker system. In a real system, time delays often exist in the wave making process. Thus a delay compensation term to the transfer function is proposed. Experimental results show that the system performs well for both regular and irregular waves with periods from 0.6 s to 2.0 s, and the absorption capability is larger than 96.5% at target wave fields.