• International Journal of Aeronautical and Space Sciences
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• 제2권2호
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• pp.39-45
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• 2001

To reduce the strength of tip vortex of the fixed wing, a horizontal wing-let splitted into two parts was utilized, and the interaction between vortices generated by these wing-lets was investigated by the hot-wire anemometry. The process of vortex forming and merging was clarified by measurements of velocity vectors and their contours at five downstream cross-sections; 0.05C(chord length), 0.2C, 0.5C, 1.0C and 2.0C. Both vortex-lets formed by each wing-lets rotate counterclockwise and merge into a larger single vortex within a short downstream distance, 0.5C in this case. The strength of the merged tip vortex turned out to become smaller than that of the plain wing tip near the vortex core.

• 한국생산제조학회지
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• 제20권1호
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• pp.23-27
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• 2011

This study analyzes about the variation of pressure and stream velocity according to the movement of tail wing. The pressure at the front part of airplane becomes lower than at the rear part and the stream velocity has decreased by being bumped against the wing of airplane. The pressure at the front part of rudder becomes higher than at its rear part according to the movement of rudder among the tail wings of airplane. The more stream velocity becomes decreased, the more rudder spreads out. As the tail wing of airplane folds, the pressure at its front part becomes higher. And the pressure at its rear part becomes lower than at its front part. The more tail wing of airplane folds, the more stream velocity becomes decreased.

• Advanced Composite Materials
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• 제17권4호
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• pp.343-358
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• 2008

This present study provides the structural design and analysis of main wing, horizontal tail and control surface of a small scale WIG (Wing-in-Ground Effect) craft which has been developed as a future high speed maritime transportation system of Korea. Weight saving as well as structural stability could be achieved by using the skin.spar.foam sandwich and carbon/epoxy composite material. Through sequential design modifications and numerical structural analysis using commercial FEM code PATRAN/NASTRAN, the final design structural features to meet the final design goal such as the system target weight, structural safety and stability were obtained. In addition, joint structures such as insert bolts for joining the wing with the fuselage and lugs for joining the control surface to the wing were designed by considering easy assembling as well as more than 20 years service life.

• 항공우주시스템공학회지
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• 제7권3호
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• pp.15-19
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• 2013

Tail wing is important to designing of civil aircrafts, because it is responsible for aircraft stability and control. Tail wing has a role in aircraft control and makes aircraft fly stably without any pilot control input. Also, designing of tail wing determine trim drag force in whole aircraft. Center of gravity(CG) of aircraft travels with various effects as placement of passenger's seats, location of cargo bay, etc. In designing horizontal tail volume, aircraft CG travel has to be considered to have margin so that it should be sized to provide adequate stability and control for the airplane's entire CG range throughout the flight envelope. Finally, it is essential to have sufficient elevator control to perform stall at forward CG for all flaps down configurations. Such stalls establish the FAR stall speed which airplane take-off and landing performance. This paper deals with the process for tail wing design regarding the aircraft CG travel and results for 95-seat type turboprop aircraft.

• 항공우주기술
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• 제10권1호
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• pp.175-182
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• 2011

100인승 이하의 쌍발 터보프롭 항공기의 날개 형상에 대한 최적 설계를 수행하였다. 최적설계는 2단계로 이뤄져 있는데 먼저 꼬리날개의 높이에 대한 방향안정성을 분석하였고 방향 안정성을 갖는 높이에 대해 순항조건에 대해 항력을 최소로 하는 날개의 최적형상을 결정하였다. 방향안정성 분석은 Vorstab를 통해 이뤄졌고, 최적형상은 Piano를 활용하여 결정하였으며 공력해석은 점성을 고려한 Fluent 코드를 활용하였다. 최적설계 결과 약 10 count의 항력을 감소하였다.

• 대한기계학회논문집B
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• 제28권7호
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• pp.800-808
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• 2004

Wind tunnel test of an airplane model with forward swept wing was done in KARI LSWT to evaluate and measure the aerodynamic characteristics of initially designed configuration. Since the given wing planform did not fully satisfy the design requirements, local flow control devices such as vortilon, vortex generator and flow fence were used to delay separation and to enhance aerodynamic characteristics. Also decision making processes of design parameters such as vertical tail boom length, the location, size and the incidence angle of horizontal tail were discussed. The general aerodynamic characteristics of forward swept wing for various control surface deflection conditions of flap, aileron and elevator were also given.

• 한국항공우주학회지
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• 제35권6호
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• pp.509-516
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• 2007

본 연구에서는 틸트로터 항공기의 날개-로터 시스템의 수학적 모델링과 자유진동 제어에 대하여 고찰하였다. 날개에 부착된 로터는 수직방향에서 수평방향으로 또는 그 반대로 틸팅각을 변경시킬 수 있다. 로터의 틸팅각, 복합재료 날개의 섬유각, 로터의 회전속도를 변수로 하여 자유진동 특성 및 압전재료를 이용한 자유진동 제어 효과에 대하여 고찰하였다. 복합재료 날개는 상자형 박판 보로 모델링 하였으며, 플랩-래그운동 사이의 연성과 인장-비틀림 운동사이의 연성이 발생하는 CUS 구조로 가정하였다. 수치해석 결과와 그에 따른 결론을 도출하였다.

• 한국항공우주학회지
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• 제45권3호
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• pp.173-179
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• 2017

본 논문에서는 모션캡쳐 카메라를 사용한 실험을 통해 날갯짓 비행체의 주 날개, 꼬리날개 구동기 특성 분석에 대하여 기술하였다. 실험은 빛이 차단된 실내에서 진행되었고 지그에 기체를 고정하여 날갯짓으로 인한 영향을 줄였다. 주 날개와 꼬리날개 끝단에 마커를 부착하였고 모션캡쳐 카메라는 입력 신호에 대한 각각의 반응을 측정한다. 실험 결과 주 날개는 날갯짓의 주파수에 따라 진폭이 변하는 경향을 보였고, Modified Strip Theory에 실험 결과와 비행체 제원을 적용하여 양력 및 추력 발생 시뮬레이션을 구현 하였다. 꼬리날개는 종 횡축별로 스텝 신호를 인가하여 이에 따른 결과를 2차 전달함수 형태로 정의하였고, 각 축별로 구동기의 구조 차이로 인하여 최종 응답시간, 오버슈트, 최대값 등에서 차이를 나타내는 것을 확인하였다.

• 대한임베디드공학회논문지
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• 제14권1호
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• pp.25-31
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• 2019

An underwater glider is a type of autonomous unmanned vehicle and it advances using a vertical zig-zag glide. For this purpose, the position of an internal battery is regulated to control its attitude, and the amount of water in a buoyancy bag is regulated to control the depth. Underwater glider is suitable for a long-distance mission for a long time, because the required energy is much smaller than the conventional autonomous unmanned vehicle using propeller propulsion system. In this paper, control of horizontal tail wing is newly added to the conventional battery position and buoyancy control. The performance of the proposed controller is shown through Matlab simulation.

• 한국항공우주학회지
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• 제35권2호
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• pp.149-156
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• 2007

본 연구에서는 한국의 차세대 해양 운송 시스템 구축의 일환으로 개발 중인 소형 위그선의 주익 및 수평 미익의 구조 설계 및 해석을 수행하였다. 구조안정성과 경량화를 위해 스킨-스파-폼 샌드위치 구조를 채택하였으며 탄소/에폭시 복합재료를 주로 적용하였다. 구조 안전성 및 안정성 평가를 위해 상용 유한 요소 코드인 NASTRAN을 활용하였으며 단계별 구조 설계 변경을 통해 최종 설계 요구 조건을 만족시켰다. 또한 동체와 연결 부위는 용이한 장탈착과 20년 이상의 피로 수명을 보장할 수 있도록 8개의 고강도 볼트를 이용한 삽입 볼트 형태의 구조를 채택하였다.