Abstract
Japanese traditional boats going ahead by human power have high efficiency in comparison with the other human-powered boats. The reason why the Japanese traditional boat has high efficiency is to use lift as propulsive force. In this study, we have manufactured a small model of a Japanese traditional boat for experiment to examine the specification. Models of oar have been made by using a 3D printer. Each of models of oar is different from cross-sectional shape. The electrical power consumption and net propulsive force have been measured in the experiment. In addition, by using CFD analysis of water flow around each oar, lift, drag force and lift-to-drag ratio have been calculated. By comparing the experimental results and CFD results, it has been found that which cross-sectional shape of oar is suitable for the propulsion of Japanese traditional boats. This study will be useful to develop an underwater robot which applies the principles of the oar.
