The KSFM Journal of Fluid Machinery (한국유체기계학회 논문집)

Korean Society for Fluid machinery (한국유체기계학회)
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The Leakage and Rotordynamic Analysis of A Combination-Type-Staggered-Labyrinth Seal for A Steam Turbine

스팀 터빈용 조합형 엇갈린 래버린스 실의 누설량 및 동특성 해석

  • 하태웅 (경원대학교 건축설비 기계공학부) ;
  • 이용복 (한국과학기술연구원 트라이볼로지 연구센터) ;
  • 김승종 (한국과학기술연구원 트라이볼로지 연구센터) ;
  • 김창호 (한국과학기술연구원 트라이볼로지 연구센터)
  • Published : 2004.12.01
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Abstract

Governing equations and numerical solution methods are derived for the analysis of a combination-type-staggered-labyrinth seal used in high performance steam turbines. A bulk flow is assumed for each combination-type-staggered-labyrinth cavity. Axial flow through a throttling labyrinth strip is determined by Neumann's leakage equation and circumferential flow is assumed to be completely turbulent in the labyrinth cavity. Moody's wall-friction-factor formula is used for the calculation of wall shear stresses. For the reaction force developed by the seal, linearized zeroth-order and first-order perturbation equations are developed for small motion near the centered position. Integration of the resultant first-order pressure distribution along and around the seal defines the rotordynamic coefficients of the combination-type-staggered-labyrinth seal. Theoretical results of leakage and rotordynamic characteristics for the IP4-stage seal of USC (ultra super critical) steam turbine are shown with the effect of sump pressure, the number of throttling labyrinth strip, and rotor speed.

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References

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