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arXiv · 1901.05931

Laboratory investigations on the resonant feature of `dead water' phenomenon

Karim Medjdoub·Imre M. Jánosi·Miklós Vincze
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Abstract

Interfacial internal wave excitation in the wake of towed ships is studied experimentally in a quasi-two layer fluid. At a critical `resonant' towing velocity, whose value depends on the structure of the vertical density profile, the amplitude of the internal wave train following the ship reaches a maximum, in unison with the development of a drag force acting on the vessel, known in the maritime literature as `dead water'. The amplitudes and wavelengths of the emerging internal waves are evaluated for various ship speeds, ship lengths and stratification profiles. The results are compared to linear two- and three-layer theories of freely propagating waves and lee waves. We find that despite the fact that the observed internal waves can have considerable amplitudes, linear theories can still provide a surprisingly adequate description of subcritical-to-supercritical transition and the associated amplification of internal waves.

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Karim Medjdoub, Imre M. Jánosi, Miklós Vincze. 2019-01-17. Laboratory investigations on the resonant feature of `dead water' phenomenon. https://doi.org/10.1007/s00348-019-2830-2

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