수치해석을 이용한 타 형상에 따른 수중 운동체의 조종 성능 연구

Abstract

Maneuvering performance is one of the key hydrodynamic factors that determine the safety and functionality of an underwater vehicle. Therefore, accurately predicting maneuvering performance is essential for hull design. In this study, computational fluid dynamics(CFD) was used to analyze the maneuvering performance of a freely running underwater vehicle. The BB2 submarine was selected as the target model at a 1/18.35 scale. The commercial software STAR-CCM+ was used for the simulations, and the virtual disk method was applied to model the propeller thrust. For validation, resistance and self propulsion simulation were performed at the same speed and compared with model test results. Based on these results, turning and zig-zag tests were conducted. A six-degree-of-freedom(6-DOF) condition was applied, where a PD controller was used to control the rudder. Two different rudder configurations – X-rudder and cruciform rudder – were considered while all other conditions, including hull shape, speed, and control gain values, were kept identical to compare the differences caused solely by the rudder type. To implement the rotational motion of the rudder, the sliding mesh method was applied for the X-rudder, while the overset mesh method was used for the cruciform rudder to avoid interference between the rotating region and the hull. Finally, the maneuverability of the underwater vehicle was compared for the two rudder configurations, and in addition, hydrodynamic coefficients due to rudder deflection were analyzed in detail.