Canoe paddle resonance characteristics and modelling

Abstract

Canoe paddles have been in continuous use for thousands of years. Over that period, the paddle has remained virtually unchanged in basic form and materials. Today, paddles are produced in many different designs by a large number of manufacturers. Prominent within the many factors differentiating the best paddles from the worst is their propensity to resonate during use. This resonance has been so prevalent historically that it has been given its own name: a paddle’s song. The major drawback with paddle resonance is that it is accompanied with the penalty of increased fluid resistance. Paddle manufacturers have long tried to reduce or eliminate paddle resonance, but it is still recognized by paddlers as a significant factor in choosing an optimal paddle. This study examined canoe paddle resonance in laboratory, open water, and computer modelling environments. The goal was to investigate the characteristics of this commonly occurring phenomenon and validate the techniques used in the modelling studies. The hypothesis tested in this paper is that by employing and comparing scientific measurement and modelling techniques it would prove possible to examine the relationship between physical paddle structure, fluid-based excitation, and resonance observed during paddle use. The obtained results indicated that the paddle being studied displayed a number of different characteristic resonance patterns or modes depending on the velocity of water flow over the blade. The results of the computer modelling studies on the resonance modes were found to be in good agreement with the observations made in laboratory and open water experiments.