Design, Fabrication and Testing of the Composite Pitch-Adapting (Flex) Propellers

Pitch adapting (Flexible) composite propellers offer the potential for improved performance over metal propellers in cavitation and vibration performance while reducing weight and manufacturing cost. As the propeller rotates in the non-uniform (circumferentially-varying) flow field, the blade deforms in response to the hydrodynamic loading, resulting in reduced cavitation and hull vibration. Using high-performance carbon fiber reinforced plastic (CFRP) as a blade material not only reduces the propeller weight but also increases the strength. The design and the analysis of two sets of rigid and flexible composite propellers are addressed. The fabrication was performed by A.I.R. using CFRP. The tests were carried out at the NSWCCD 36-in water tunnel. The test results show that the powering and cavitation performance of flexible propellers can be better than those of rigid propellers.