Studies on Towing Test Related to Predict of Resistance and Motion of Small Fishing Boats at High Froude Number

用拖曳水箱进行小渔船高速模型试验。在拖航中，我们采用了两种方法使模型抽筋。第一种是固定船舶所有运动模式而不允许船舶移动的方法(称为固定测试)。第二种是解除升沉、俯仰和修正其他模式的方法(称为自由试验)。本研究的主要目的如下。目的：探讨在高模数下拖曳一个非常小的模型的方法。并开发以适当的方式携带模型的设备。研究在自由试验中测得的运动变化与固定试验中升力矩和纵倾力矩数据之间的相关性。我们设计的模型拉升和抽筋机构，对于用很小的模型进行拖曳试验是非常有用的，因此，对于高FN速度的试验是非常有用的。从固定试验和自由试验两次拖航试验中可以看出，这两次拖航试验是密切相关的。自由试验中的运动变化可以从固定试验中测得的力和运动粗略地估计出来。

The model tests of small fishing boats at high speed carried by means of towing tanks. We adopted two ways to cramp the model in towing. The first is the way that fixes all mode of ship's motions and don't allow the ship to move (named fixed test). The second is the way that release heaving and pitching and fixes the other modes(named free test). The principal purposes of this study are follows.1. To investigate the approach to tow a very small model at high Fround Number. And to develop the equipment to carry the model in proper manner.2. To research on the correlation between the change of motions measured in free test and the data of lift and trim moment in fixed test.The details of this experimental study can be summed as follows.1. The mechanism, we designed, that pulls up the model and cramps is very useful to towing test using very small model, therefore, for tests at high Fn speed.2. We could see from the two towing test, fixed and free tests, that these tests are closely relate each other. The change of motions in free tests can be roughly estimated from the forces and motions measured in fixed test.