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Axial Force Measurement of Gas Foil Thrust Bearings Supporting a Turbo-compressor

터보 압축기를 지지하는 가스 포일 스러스트 베어링의 추력 측정

  • Nam Kyu Kim (Graduate School, Dept. of Mechanical Systems Engineering, Kookmin University) ;
  • Min Woo Lee (School of Mechanical Engineering, Kookmin University) ;
  • Yongbum Kwon (Graduate School, Dept. of Mechanical Systems Engineering, Kookmin University) ;
  • Tae Ho Kim (School of Mechanical Engineering, Kookmin University)
  • 김남규 (국민대학교 대학원 기계시스템공학과) ;
  • 이민우 (국민대학교 기계공학부) ;
  • 권용범 (국민대학교 대학원 기계시스템공학과) ;
  • 김태호 (국민대학교 기계공학부)
  • Received : 2024.10.30
  • Accepted : 2024.10.31
  • Published : 2024.10.31

Abstract

Gas foil thrust bearings (GFTBs) are aerodynamic bearings that use gas as a lubricant to support axial forces in noncontact states. To enhance the load support performance of GFTBs, researchers conduct studies requiring experimental load measurements in mechanical systems for verification. This study measures the thrust of a high-speed turbo-compressor supported by a gas-foil thrust bearing. We examine the effect of temperature changes on the load cell installed inside the compressor before the experiment. First, we supply heat to the compressor using a heating gun to stabilize the load cell temperature. We then apply a static load using a push-pull gauge. Next, we derive the load cell temperature compensation equation based on the difference between the measured and applied loads as temperature varies. The results show that when maintaining the rotor speed at 80 krpm before stopping, the measured load gradually decreases and converges to -108 N, which is lower than the initial 0 N. This decline is owing to the temperature increase in the load cell near the bearing due to the viscous shear friction between the bearing and thrust runner during rotation. Finally, after applying temperature compensation, the thrust increases with increasing rotational speed of the rotor.

Keywords

Acknowledgement

본 연구는 기업체-국민대 간 산학연구과제와 2024년도 산업통상자원부의 재원으로 한국 에너지기술평가원(KETEP)의 "AI/ICT 기반 가변형 유체기기 설계, 상태진단을 위한 기반 플랫폼 기술 및 운영관리 시스템 개발" 연구과제(2021202080026D)에서 일부 지원받아 수행되었습니다. 이에 관계자 여러분께 감사드립니다.

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