Determining basic characteristics of bulk carriers at the early stages of design

Abstract

This paper considers the task to determine the basic characteristics of bulker vessels. Available studies that define the main characteristics of ships were analyzed. The complexity of the task to choose a prototype in the process of determining the basic characteristics of bulk carriers at the initial stages of design has been shown. The accepted assumption implied that each ship in the sample (a ship database) was designed in such a way that some operational qualities and/or economic characteristics of a vessel are optimal in a certain sense. To solve the task, stochastic factor analysis was used, and the method of principal components was applied, which makes it possible to identify numerical characteristics that affect the parameters of the entire system but are not clearly observed. The factors were compiled that are dimensionless sets of characteristics of sample vessels, which are, in fact, new phase orthogonal coordinates of the problem with unequal variances of the sample along the coordinate directions. Evaluating the significance of correlations of factors and vectors of the sample data makes it possible to discard factors that have a weak influence on the values of the parameters of the sample vessels. Thus, the model of the problem is simplified while preserving essential connections. The analysis of the calculation data revealed that the number of significant factors due to the use of the principal component method decreased from 7 to 3. It was determined that the ships of the same designers are indeed grouped by the value of the factor sets. In the absence of an original algorithm for determining the main characteristics of the vessel at the initial stage of design, the application of the described factor analysis procedure should help with the definition of the main factors that affect the quality of the design. Further, it is possible to apply more subtle mechanisms for project optimization according to selected economic and technical parameters. The data of the numerical calculation of integrated characteristics of the ship are given