• 제목/요약/키워드: Whirling

검색결과 96건 처리시간 0.025초

전자석을 이용한 가제어형 스퀴즈필름댐퍼 (Controllable Squeeze Film Damper Using an Electromagnet)

  • 안영공;하종룡;양보석;김동조
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 춘계학술대회논문집
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    • pp.510-513
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    • 2003
  • The paper represents the stability of a rotor system with the squeeze film damper (SFD) using an electromagnet. The electromagnet is installed in the inner damper of the SFD. The proposed SFD has basically property of a conventional SFD and variable damping property according to variation of the applied electric current. Therefore, when the applied current controlled, the whirling vibration of the rotor system can be effectively reduced in a wide operational speed range. In the present work, the performance of the SFD was experimentally investigated according to changing the magnetic field strength. When the applied current increased, the whirling amplitude greatly reduced and the damping ratio also increased.

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축어긋남이 있는 유연복합재 고속구동축의 특성 분석 (Characterization of a Misaligned Supercritical Shaft of Flexible Matrix Composite)

  • 홍을표;신응수
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 춘계학술대회논문집
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    • pp.107-113
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    • 2003
  • This research is to investigate the performance of a flexible matrix composite driveshaft with respect to shaft design parameters such as the number of layers, ply orientations, and material properties. A finite element formulation is utilized to estimate the allowable misalignment under given driving torque, the maximum temperature at steady states, and external damping for ensuring whirling stability under supercritical speed. Results indicate that the system performance can be greatly affected by the shaft laminate parameters, especially the ply orientations. Several sets of shaft parameters that will provide satisfactory overall system performance are derived.

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초전도 자기베어링-플리이휠 시스템의 회전체 해서 및 실험 (Rotordynamic Analysis and Experiment of Superconducting Magnetic Bearings-Flywheel System)

  • 김종수;이수훈
    • 한국정밀공학회지
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    • 제16권9호
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    • pp.104-109
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    • 1999
  • The flywheel energy storage system using superconducting magnetic bearings is a device to store electrical energy as rotatioal kinetic energy by motor and to convert it to electrical energy by generator when it is necessary. The rotordynamic analysis should be performed with an adequate analytical model and equations of motion to identify the stable driving condition and the dynamic behavior. The critical speed and the unbalance response of superconducting magnetic bearings-flywheel system are studied in this paper. The analytical results show that the system has one forward whirling mode and two backward whirling models below 500rpm. The maximum displacement 0.75mm is detected at the first forward mode (385rpm)through unbalance response analysis. The analytical results are compared with the experimental result by the spin-down test. The experimental result shows that the maximum displacement is 0.7mm at 370rpm.

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전자석을 이용한 가제어형 스퀴즈필름댐퍼 (Controllable Squeeze Film Damper Using an Electromagnet)

  • 안영공;하종룡;양보석;김동조
    • 한국소음진동공학회논문집
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    • 제13권6호
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    • pp.484-489
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    • 2003
  • The paper represents stability of a rotor system with the squeeze film damper (SFD) using an electromagnet. The electromagnet is installed in the inner damper of the SFD. The proposed SFD has basically the property of a conventional SFD and variable damping property according to variation of the applied electric current. Therefore, when the applied current Is controlled, the whirling vibration of the rotor system can be effectively reduced in a wide operational speed range. In the present work, the performance of the SFD was experimentally investigated according to changing the magnetic field strength. As the applied current increased, damping ratios increased, while whirling amplitudes greatly reduced.

추진축계 횡진동 1차 기진력에 의한 여객.차도선의 선체 상부진동 (Passenger & Car Carrier's Superstructure Vibration induced by the 1st order Excitation of Whirling Vibration on the Propulsion Shafting System)

  • 이돈출;고재용;김정렬
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2000년도 추계학술대회논문집
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    • pp.301-306
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    • 2000
  • Small passenger and car carrier ships are mainly used as a connection way between land and small islands. And these ships should be designed to enlarge the capacity of passenger and car loading within limited space and draft. So the resonances of various vibrations exist in normal operation range of engine and propulsion shafting. In this paper, hull's superstructure vibration which was especially induced by the 1st order excitation of whirling vibration on the 2-engines and 2-propulsion shafting systems is introduced. Also these are verified via the theoretical analysis using transfer matrix method and FEA software ANSYS and its vibration measurement.

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선박 추진축의 선회임계속도에 관한 연구 (A Study on the Whirling Critical Speeds of Marine Propeller Shafts)

  • 김용철;이건도
    • 대한조선학회논문집
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    • 제31권2호
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    • pp.29-37
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    • 1994
  • 본 논문에서는 선박 추진축계의 정확한 임계속도 추정을 위한 모델링방법 및 해석방법을 제시하였다. 해석방법으로서는 전달행렬법을 사용하여 추진축의 임계속도 및 선회운동응답을 구하였다. 또한, Jasper식과 Panagopulos식 등과 같은 간이 추정식들의 타당성을 검증하기 위하여 수치계산을 수행하였다. 일반적인 선박 추진축계에 대한 수치계산 결과로부터 축의 임계속도는 저어널베어링의 위치 및 지지조건에 민감함을 알 수 있었다.

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