LCT에서 방향타 동력계를 이용한 평판 및 비틀림 방향타 특성의 실험적 연구

Abstract

In order to investigate force and cavitation characteristics for the flat & twisted rudders in Large Cavitation Tunnel (LCT), the rudder dynamometer was designed and manufactured. The measuring capacities of lift, drag and moment are ±1000N, ±2000N and ±150N-m, respectively. The present dynamometer uses the actuator with harmonic drive to control the rudder angle without backlash. As the target ship is the military ship with twin shaft, each dynamometer was installed above the port & starboard rudders. After the installation of the model ship with all appendages, it was conducted the model test composed of rudder force measurement and cavitation observation was conducting for the existing flat rudder & thedesigned twisted rudder. While the flat rudder showed the big difference of lift & moment between port & starboard, the twisted rudder presented the similar trend. The cavitation of the twisted rudder showed better characteristics than that of the flat rudder. Another model tests were conducted to investigate rudder performance by the change of the design propeller. There was little difference in rudder performance for the design propellers with slight geometric change. Through the model test, the characteristics of the flat & twisted rudders were grasped. On the basis of the present study, it is thought that the rudder with the better performance would be developed.