Síntese de cascos de embarcações através de métodos de otimização aplicados a curvas B-Spline.

Abstract

This article presents a flexible and efficient tool to the field of ship project and preliminary design by using an approach of parametric modeling of hull forms. The state of the art of design of hulls consists in an iterative process where, first, geometric, stability and hydrodynamic parameters are defined. After that, the hull is modeled through parametric curves, simulated in a performance analysis software, and, after that, it is taken the decision to optimize the initial parameters. The cycle repeats until it reaches the desired result. This work deals with the part of parametric modeling, and is capable to generate, in an automatic way, optimized curves that compose the design of the hull of a yacht. The tool receives high level parameters, such as non-dimensional ratios, coefficients and restrictions, and draws a three-dimensional hull, intrinsically fair, fulfilling all the specified parameters. A methodology for the design of sailboats is presented together with B-Splines curves, submitted to an optimization algorithm, using fairness criteria as the objective function. The optimization problem of B-Splines curves is not linear, because of its mathematical formulation, the objective function and constraints adopted. Therefore, a method of Sequential Quadratic Programming is used. For the optimization of the main parameters of the hull, a cost-effective methodology, based on the Surface Response Method, is proposed, optimizing a merit criterion, such as, the residuary resistance, changing two parameters of the hull. The interface with CAD software is implemented in order to allow other analyses, such as surface curvature, and the design of the other parts of the boat. The drawing also can be transformed into a solid model, and integrated with a CAM software to be ready for its manufacturing.

Desenvolvimento de uma ferramenta para otimização paramétrica da resistência hidrodinâmica de veleiros através da série de Delft.

“…Contudo, por não propor uma solução sistemática e orientada, este método não é propriamente classificado como otimização. O mesmo não pode ser dito do trabalho de Barbarini (2007), que desenvolveu um algoritmo para geração paramétrica de cascos de veleiros a partir de um conjunto reduzido de dimensões. Este algoritmo, por sua vez, é vinculado a cálculos de resistência através da série de Delft, relacionando as dimensões do casco ao seu desempenho ao longo do processo.…”