RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • KCI등재

        Development of Efficient Dynamic Aeroelasticity Model for High Fidelity Pointing Accuracy Assessment of VLBI Earth-Based Radio Antennas

        Nieto Michelle Guzman,Thomas Paul V.,ElSayed Mostafa S. A.,Saad Mohamed,Brown Gary L.,Hilliard Lawrence M. 한국항공우주학회 2020 International Journal of Aeronautical and Space Sc Vol.21 No.3

        Modern Earth-based radio antennas of very-long-baseline interferometry system are furnished with robust control systems for their pointing control. Their pointing accuracy is critical to the quality of the radio wave-front captured. External disturbances, particularly those of wind gusts, produce a non-negligible dynamic aeroelastic response that degrades its pointing accuracy, and yet are not mitigated by the antenna’s control system. In this paper, a high fidelity and efficient dynamic aeroelastic model of an earth-based antenna is developed which is used to study the effects of wind gusts on the antenna’s pointing accuracy. Model order reduction of the antenna structural model is carried out using Craig–Bampton method taking into consideration the dominant modal characteristics of the antenna. The aerodynamic forces are approximated using the 2D Doublet-Lattice Method. The Davenport Spectrum is used to model aerodynamic turbulences near the earth surface. The developed dynamic aeroelastic model is employed to investigate the effects of discrete and random gusts on the pointing accuracy of the antenna. It is found that the deviation in the pointing angle is more prominent in the z (azimuth) direction and it displays a quadratic dependency with respect to the mean wind speed. This behavior is attributed to the inertial component of the aeroelastic response solution represented by the gravitational field acting on the center of gravity of the main reflector and the counterweights. The developed efficient aeroelastic model can be integrated into the antenna control system for its response prediction and mitigation.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼