This study analyzed the duct characteristics of hubless rim-driven propeller (RDP) used in underwater robots. In the previous study, flow visualization experiments were performed with an advancing ratio of 0.2 to 1. The vortex at the front of the duct increased in strength while maintaining its size as the advancing ratio decreased. Therefore, it is necessary to study the optimization of the duct shape. Conventional propeller thrusters use acceleration/deceleration ducts to increase their efficiency. However, unlike conventional propellers, it is impossible to apply to airfoil acceleration/deceleration ducts due to the RDP structure. In this study, duct wake flow characteristics, thrust force, and efficiency according to the duct shape of RDP were analyzed using numerical analysis techniques. Duct design is limited and six duct shapes were designed. As a result, an optimized duct shape was designed considering duct wake flow characteristics, thrust force, and efficiency. The shape that the outlet width of the RDP was kept constant until the end of the duct showed higher thrust force and efficiency.

• 편용범(한국수산해양공학연구소 연구원) | Yong-beom PYEON (Researcher, Korea Institute of Fisheries and Ocean Engineering, Busan 48508, Korea)
• 배재현(국립수산과학원 수산공학과 연구사) | Jae-Hyun BAE (Researcher, Fisheries Engineering Research Division, National of Fisheries Science, Busan 46083, Korea)
• 김형호(경상국립대학교 기계공학부 조교수) | Hyoung-Ho KIM (Assistant Professor, School of Mechanical Engineering, Gyeongsang National University, Gyeongnam 52725, Korea)
• 이창제(한국해양대학교 해사산업연구소 연구교수) | Chang-Je LEE (Research Professor, Institute of Maritime Industry, Korea Maritime and Ocean University, Busan 49112, Korea) Corresponding author