Abstract: The article presents an evaluation of the operational rolling test as an experimental method for determining the ship’s metacentric height. The quantitative evaluation was based on the results of solving the ship’s rolling equation with one degree of freedom. The significant influence of mass distribution, and consequently the value of the ship’s moment of inertia, on the rolling period was indicated. The need to modify the International Maritime Organization’s recommendations regarding the relationships used when calculating the ship’s metacentric height based on the rolling test was suggested.1. INTRODUCTION
Shaping safety during the operational phase of an object is called safety management. An important element of the safety management process is the effective control of the object’s technical condition, a concept that also includes the assessment of ship stability [1]. The assessment of a seagoing vessel’s stability is therefore part of the crew’s activities carried out to ensure the ship maintains the required level of safety during navigation.
In maritime practice, the assessment of ship stability is performed based on standards defined by ship classification institutions. These standards result from the recommendations of resolution A749(18) of the IMO (International Maritime Organization), which, together with subsequent amendments, forms the Intact Stability Code (ISC) [2]. Parameters defining the shape of the righting lever curve are subject to standardization, including the metacentric height, which is linked to the righting lever curve via the metacentric triangle.
The primary method used to determine the value of the metacentric height is the calculation method. It consists of preparing a mass calculation table to determine the position of the ship’s center of gravity, and then using the ship’s hydrostatic data to read the ordinate of the initial transverse metacenter.
Due to the uncertainty of data regarding cargo mass, and often even the unreliability of this data provided by the shipper, the actual position of the ship’s center of gravity may differ significantly from that calculated in the mass calculation table [6]. This is one of the most significant reasons why the metacentric height is determined not only based on calculations but also experimentally. (…)
The article contains 17,346 characters.
Source: Logistyka Magazine