• Title/Summary/Keyword: 피치변경

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The Study of Advanced Propeller Blade for Next Generation Turboprop Aircraft -Part I. Aerodynamic Design and Analysis (차세대 터보프롭 항공기용 최신 프로펠러 블레이드 연구 -Part I. 공력 설계 및 해석)

  • Choi, Won
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.40 no.12
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    • pp.1017-1024
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    • 2012
  • The aerodynamic design and analysis on advanced propeller with blade sweep was performed for recent turboprop aircraft. HS1 airfoil series are selected as a advanced propeller blade airfoil. Adkins method is used for aerodynamic design and performance analysis with respect to the design point. Adkins method is based on the vortex-blade element theory which design the propeller to satisfy the condition for minimum energy loss. Propeller geometry is generated by varying chord length and pitch angle at design point of target aircraft. Advanced propeller is designed by apply the modified chord length, the tip sweep which is based on the geometry of conventional propeller. The aerodynamic characteristics of the designed Advanced propeller were verified by CFD(Computational Fluid Dynamic) and evaluated to be properly designed.

Modeling and Controller Design for Attitude Control of a Moving Satellite (이동하는 위성의 자세제어를 위한 모델링 및 제어기 설계)

  • Lee, Woo-Seung;Park, Chong-Kug
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.37 no.1
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    • pp.19-29
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    • 2000
  • Because the previous simulation tool for attitude control of satellite was designed for the modeling of rigid body and PD controller, the attitude error can be made more than the limitation value for keeping for communication link, and then the communication link can be lost at moving of satellite. So, for rapid attitude restoration and design of stable and modernized controller, the modelling of rigid body and flexible body structure for moving GEO and LEO satellites were performed. Also the minimum time controller is designed for the rapid restoration of attitude error at communication broken and to minimize the disconnection period from ground communication system during the satellite stationkeeping. The linear regulator is designed using the space state vector that is better than accuracy and stability of PD controller. Firstly the simulation was performed for comparison of the rigid and stability of PD controller. Firstly the simulation was performed for comparison of the rigid and flexible models using PD controller and the case of the pitch angle changing by ground command, and the case of the periodic north-south stationkeeping are performed for the analysis of response characteristics of each controller when the attitude is changed. As a result, the flexible body model represents more sililar results of real situation than the rigid body model. The minimum time controller can restore 7 times rapidly than PD controller for its lost attitude. The linear regulator has several merits for capability of adaptation against the external disturbance, stability and response time. In future, we can check the estimated results using this satellite model and controller for real operation. Futhermore the development of new controller and training can be supported.

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Improvement of Flight Safety by Horizontal Stabilizer Design Improvement of Rotorcraft (회전익 항공기 수평 안정판의 설계 개선을 통한 비행 안전성 향상)

  • Lee, Yoon-Woo;Kim, Dae-Han;Jang, Min-Wook;Hyun, Young-Jin;Lee, Sook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.6
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    • pp.134-141
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    • 2019
  • This paper is a study on design improvement of rotorcraft horizontal stabilizer. The rotorcraft horizontal stabilizer stabilizes the behavior of the pitch, yaw, etc. from the aircraft. Because of this role, horizontal stabilizers are a major component (Flight Safety Part) that affects flight safety on rotorcraft. However, when the rotorcraft was operated in domestic, cracks were found in the inner structure of the horizontal stabilizer and design improvement was needed. In this paper, we identified the two causes of the horizontal stabilizer crack defects through fracture analysis and structural analysis. The first is the tightening torque when the bolt is tightened, and the second is the lead-lag behavior of aircraft. In order to improve these two causes, bolt fastening method, flange structure and thickness were changed and composite ring was applied. In order to verify the design improvement, the structural analysis was performed and the structural strength was improved. Also Fatigue analysis of the internal structure (Rib 1) was performed and it was confirmed that the requirements were satisfied.