CFD를 이용한 KRISO 추진효율 향상 장치(K-duct) 형상 특성에 관한 연구

• Published in: 大韓造船學會 論文集 Vol. 55; no. 6; pp. 474 - 481
• Main Authors: 김진욱(Jin-wook Kim), 서성부(Sung-Bu Suh)
• Format: Journal Article
• Language: Korean
• Published: 대한조선학회 2018
• Subjects: 조선공학; K-duct; RANS method; Energy saving device(에너지 절감 장치); Pre-swirl duct; Self-propulsion(자항); Computational fluid dynamics(전산유체역학)
• ISSN: 1225-1143; 2287-7355
• DOI: 10.3744/SNAK.2018.55.6.474

This paper is to compare by numerical analysis the flow characteristics and propulsion performance of stern with the shape change of K-duct, a pre-swirl duct developed by Korea Research Institute of Ships & Ocean Engineering (KRISO). First, the characteristics of the propeller and the resistance and self-propulsion before and after the attachment of the K-duct to the ship were verified and the validity of the calculation method was confirmed by comparing this result with the model test results. After that, resistance and self-propulsion calculations were performed by the same numerical method when the K-duct was changed into five different shapes. The efficiency of the other five cases was compared using the delivery horsepower in the model scale and the flow characteristics of the stern were analyzed as the velocity and pressure distributions in the area between the duct end and the propeller plane. For the computation, STAR-CCM +, a general-purpose flow analysis program, was used and the Reynolds Averaged Navier-Stokes (RANS) equations were applied. Rigid Body Motion (RBM) method was used for the propeller rotating motion and SST $k-{\omega}$ turbulence model was applied for the turbulence model. As a result, the tangential velocity of the propeller inflow changed according to the position angle change of the stator, and the pressure of the propeller hub and the cap changes. This regulated the propeller hub vortex. It was confirmed that the vortex of the portion where the fixed blade and the duct meet was reduced by blunt change.