Abstract: A novel design concept is proposed to improve the efficiency of traditional boat propellers, and a propeller with self-reconfigurable structure is designed, its blades can open and close automatically to satisfy the need of water propelling. The mechanism of this new-style propeller is analyzed and the configurations in different working states are studied, and three of which are presented. Assuming that the propeller rotates at an even speed in idealized flood, the trajectory of a certain point on the blade is obtained according to the theory of flood dynamics, and the motion analysis of the propeller blade mechanism is performed. According to the characteristics and working principle of this new propeller system, the induced velocity, thrust and torque are derived on the basis of the lifting line theory and blade elements theory, the hydrodynamic performance analysis model is built and simulated. Efficiency of the propeller with self-reconfigurable structure is calculated. A comparative study between this new style propeller and the traditional propellers shows the superiority of the former.

Key words: Hydrodynamics, Propeller, Self-reconfigurable mechanism, Structural design