On the coupled time-harmonic motion of a freely floating body and water covered by brash ice. (14th April 2016)

• Record Type: Journal Article
• Authors: Kuznetsov, Nikolay; Motygin, Oleg
• Is Part Of: Journal of fluid mechanics. Volume 795(2016:May)
• Page Start: 174
• Page End: 186
• Publication Date: 2016-04-14
• Subjects: surface gravity waves, -- waves/free-surface flows, -- wave–structure interactions; Fluid mechanics -- Periodicals; 532.005
• DOI: 10.1017/jfm.2016.183
• Languages: English
• ISSNs: 0022-1120

Abstract

Abstract : A mechanical system consisting of water covered by brash ice and a body freely floating near equilibrium is considered. The water occupies a half-space into which an infinitely long surface-piercing cylinder is immersed, thus allowing us to study two-dimensional modes of the coupled motion, which is assumed to be of small amplitude. The corresponding linear setting for time-harmonic oscillations reduces to a spectral problem whose parameter is the frequency. A constant that characterises the brash ice divides the set of frequencies into two subsets and the results obtained for each of these subsets are essentially different. For frequencies belonging to a finite interval adjacent to zero, the total energy of motion is finite and the equipartition of energy holds for the whole system. For every frequency from this interval, a family of motionless bodies trapping waves is constructed by virtue of the semi-inverse procedure. For sufficiently large frequencies outside of this interval, all solutions of finite energy are trivial.