Pages 121-132
Rowing a shell eight boat is analysed by means of the technological approach from its basic principles to the actual styles of rowing. An evaluation method for strong oarsmen and a rule of selecting oars appropriate for the crew and the speed are obtained. The motion of a boat and oars are dynamically analysed and are numerically simulated. A rational definition of propulsive efficiency for rowing boats is introduced. By using the technological concept of the propulsive efficiency the optimal style of rowing is proposed through the simulations performed under various conditions relating to rowings. The important results obtained from the analysis and the simulations are as the followings: the fluctuations of boat speed in a stroke of rowing are mainly due to the moving of the center of weight of the crew sitting on sliding sheets, schemes of decreasing the speed fluctuation are effective for reducing the boat resistance and attaining a gain of fast boat speed, the main part of the thrust generated by an oar is due to the lift acted on the blade surface, the obtained optimal propulsive efficiency achieves 75 to 80%, shortening the race record muchmore demands the drastic horse power augumentation of the crew, the delicate difference of the moving of crew's weight, the angle of oar and the timing at the catch have a great effect on the propulsive efficiency.
