Approximation of the wave spectra of various vessels at different courses based on the vessel's rocking records

Abstract

The article provides data on the approximation of the final wave spectra, depending on the uniform frequency interval, for various vessels in different hydrometeorological conditions in different parts of the world's oceans. The wave spectra themselves were obtained from the records of the ships' rolling during their operational voyages. In other words, the ships were used as wave buoys, and the wave patterns at the ship's location were determined based on the rolling data. The time intervals were chosen to ensure that the ships' courses remained consistent and the wave patterns at the ship's location did not significantly change.

The solution of this problem is necessary in order to determine the amplitude-frequency characteristic of the vessel under the given load in the conditions of an operational voyage, and to optimize the course and speed of the vessel based on the conditions of safe navigation, preservation of the vessel and cargo.

Unfortunately, ships on a voyage are always in a situation where the draft changes constantly due to the consumption of fuel, lubricants, provisions, and sometimes the amount of cargo (especially for container ships). In addition, the hydrometeorological conditions at the ship's location also change constantly. As a result, the stability data provided for the departure of the ship may change significantly during the voyage, especially if it is a long one.