Study of the influence of the vessel stern shape on its hydrodynamic characteristics

Abstract

Determining the main dimensions of the small vessels while designing is an important and difficult task due to the large number of mutually exclusive factors affecting the hydrodynamic characteristics of such vessels. The existing patterns for determining the length, width and draft of small vessels are quite general. This complicates their usage for the vessel of a specific design. In this case, it is necessary to check technical solutions, one of the ways that may be implied is the usage of computational fluid dynamics (CFD) methods. This paper presents the results of the numerical simulation of boat movement in the transient mode with Froude numbers up to 1.2. The process of preparation and numerical modeling of the aerodynamics of a composite wing in the NUMECA/FineMarineTM software package is described, the choice of the turbulence model and the parameters of the computational grid, including the resolution of the boundary layer, is justified. The study of the influence of three variants of the width and shape of the aft tip on the change in draft, trim angle, wetted surface and resistance of the boat is carried out. An increase in the width of the flat planing part of the aft tip has a favorable effect on the hydrodynamic characteristics of a small vessel, even when moving in transition mode at L/B from 3.5 to 3.99. At the same time, the use of the extension of the underwater part of the aft tip requires a more detailed study.