Study on Optimum Position of Outriggers of Trimaran from Viewpoint of Wave Making Resistance

近年来，为了设计高速船舶，人们提出了许多基于非常规概念的设计思想。另一方面，为适应大型化和长距离航行的需要，在常规排水型的基础上提出了高速船的新概念。在这些基于排水型概念的船舶中，通常采用非常细长的船体形式。对于这种类型的船体，稳定性问题被认为是如此严重，多船体，如双体船是众所周知的解决方案之一。在三体船的情况下，主船体和支腿之间的兴波相互作用预计会减小兴波阻力。从兴波阻力最小的角度出发，利用非线性规划技术对小支腿的位置进行了优化。作为本课题的基础性研究，采用数学船体形式作为主船体和支腿。作为更实用的研究，还介绍了Takarada等提出的细长排水型高速船体形式作为主要的船体，并进行了与以前类似的研究。al.is在这两项研究中，基于优化结果进行了模型试验，以验证支腿的水动力效应，包括拖曳试验，波浪分析，以及纵倾和下沉测量。

In order to design high speed vessels on seaway, many ideas based on unconventional concepts are proposed in recent years. On the other hand, new concepts of high speed vessels based on the conventional desplacement type are also proposed and studied, for the purpose of sizing up and long distance voyage. In these vessels based on the displacement type concept, very slender hull forms are generally employed. For the hull of such type, however, stability problems are recognized so serious that a multi-hull, for example, a catamaran is well known as one of the solutions.In the present studies, a trimaran with small outriggers at both sides are entroduced in place of the catamaran. In the case of the trimaran, the wave making interaction between the main hull and outriggers is expected to reduce the wave making resistance. Positions of small outriggers are optimized from the view point of the minimization of wave making resistance by means of nonlinear programming technique. As fundamental studies of the present problem, mathematical hull forms are employed as the main hull and outriggers. As more practical studies, the high speed hull form of slender displacement type proposed by Takarada et al.is also introduced as the main hull, and similar studies to the previous ones are carried out. In both studies, model tests based on the optimization results are carried out to verify the hydrodynamical effect of outriggers, including towing tests, wave analyzes, and measurements of trim and sinkage.