An application of paddlewheel propulsion to a high speed craft

The paddle wheel has existed as a marine propulsor for in excess of two hundred years yet has been developed little over the last one hundred years. It could be concluded that the paddle has stagnated as a means of efficient propulsion for today‟s marine vessels. As technology develops in other areas, is it possible that paddle propulsion could find applications not yet considered? Has the paddle reached its maximum potential? This paper challenges the assumption that paddle forms of propulsion are ineffective at high rotational speeds through two means: a report on a set of trials of a relatively high powered and high rotational speed paddle wheel fastened to a purpose built 8m long planing skiff which achieved speeds in excess of 32 knots; and results from previous experimental work on paddles, carried out in the Denny experiment tank at Dumbarton, Scotland, were non-dimensionalised, replotted and applied to predict and interpret the performance of the paddle operated on the planing skiff. The paddle achieves propulsion through a relatively large swept area, thus achieving the potential for relatively high efficiency of propulsion. The present design operated with low immersion, up to about 75mm, but at lower immersions down to 5mm at higher speeds, in the wake behind an immersed transom stern. The paper reports on performance of this paddle and interprets the results in the light of the existing historical experimental results.