Transformation of the irregular wave spectrum by a step

1Gorodetska, NS
2Shcherbak, TM
1Nikishov, VI
1Institute of Hydromechanics of the NAS of Ukraine, Kyiv
2National Transport University, Kyiv
Dopov. Nac. akad. nauk Ukr. 2016, 7:49-55
Section: Mechanics
Language: Ukrainian

The transformation of the irregular wave spectrum by a step is considered. A superposition of two TMA spectra with different frequencies of spectral maxima is used as the spectrum model. The use of a linear theory (as an analog of the RDT approach) for studying the spectrum transformation under the action of an abrupt change of the depth is discussed. The coefficients of reflection and transmission over the step depending on the wave number of an incident wave are obtained on the base of the improved reduction method. The results of calculations are presented. The features of the transformed spectrum for various parameters of the task are analyzed. It is shown that the spectral amplitudes grow after the step, and the corresponding wavelengths decrease, that is, the wave become steeper.

Keywords: irregular wave motion, spectrum, surface waves, transformation
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