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Performance Analysis of Oil-lubricated Thrust Collars in Integrally Geared Compressors

증속 기어 압축기용 스러스트 칼라의 윤활 성능 해석

  • Lee, Donghyun (Dept. of System Dynamics, Korea Institute of Machinery and Material) ;
  • Kim, Byungok (Dept. of System Dynamics, Korea Institute of Machinery and Material) ;
  • Sun, Kyungho (Dept. of System Dynamics, Korea Institute of Machinery and Material)
  • 이동현 (한국기계연구원 시스템다이나믹스 연구실) ;
  • 김병옥 (한국기계연구원 시스템다이나믹스 연구실) ;
  • 선경호 (한국기계연구원 시스템다이나믹스 연구실)
  • Received : 2018.07.07
  • Accepted : 2018.09.11
  • Published : 2018.10.31

Abstract

A multi-stage compressor (MSC) is comprised of several impellers installed in the pinion gear shaft driven by a main bull gear. In the pinion shaft, a thrust collar (TC) is installed to support the thrust load. The TC makes the lubrication system simpler in the MSC; therefore, it is widely used in similar kinds of machinery. Typically, TCs are installed on both sides of the bull gear and pressure is developed in the lubricated area by creating a taper angle on the TC and bull gear surface. In the current study, we developed a numerical analysis model to evaluate the performance of the TC considering its design parameters. We sloved the Reynolds equation using the finite element method and applied the half Sommerfeld condition to consider cavitation. Based on the pressure calculated in the lubricated area, we calculated the power loss and minimum film thickness. In addition, we calculated stiffness and damping using perturbation method. We performed parametric studies using the developed model. The results of the analysis show that the maximum pressure presents in the center area of the TC and it increases with the taper angle. The area over which pressure is developed decreases with the taper angle. The results also show that there is an optimum taper angle providing minimum power loss and maximum film thickness. Additionally, the stiffness and damping decrease with the taper angle. As the applied load increases, the power loss increases and the minimum film thickness decreases. However, the stiffness and damping increase with the applied load.

Acknowledgement

Grant : 에너지 절감형 1,000 HP급 VSD 터보 공기압축기 개발

Supported by : 산업통상자원부

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