• 제목/요약/키워드: labyrinth seal

검색결과 49건 처리시간 0.031초

프로택트 컬러타입 리비린스 시일의 성능개선에 관한 실험적 연구 (An Experimental Study of Performance Improvement for Protective Collar Type Labyrinth Seal)

  • 나병철;전경진;한동철
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1997년도 춘계학술대회 논문집
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    • pp.625-629
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    • 1997
  • Sealing an oil-air mixture plays important roles to have an enhanced lubrication for high speed spindele. Current work was emphased on the investigation of air jet effect on the protective collar type labyrinth seal. To improve the sealing capability of conventional labyrinth seal,ari jet was injected against through the leakage flow. It has a combined geometry of a protective collar type and an air jet type. In this study, both of a numerical analysis by CFD (Computational Fluid Dynamics) and experimental measureements are carried out of verify sealing improvement. But of the turbulence and the compressible flow model were introduced in CFD analysis. The sealing effect of the leakage clearance and the air jet magnitude were studied for variousparameter in the experiment. The results of pressure drop in the experiment match reasonably to those of the simulation by introducing a flow coefficient. Effects of sealing improvement are explained as decreasing of effective leckage clearance by air jetting. Thus, sealing effect is improved by amount of air jetting even though clearance become larger.

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수직 온도구배를 갖는 공기 흡입 덕트의 기계적 격리기법 (Mechanical Isolation Method for an Air Intake Duct with Vertical Temperature Gradient)

  • 정치훈
    • 한국추진공학회지
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    • 제20권4호
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    • pp.87-93
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    • 2016
  • 직접 연결식(DC) 고도모의 엔진시험 수행 시, 공기 흡입 덕트와 항공용 엔진 사이에 래버린스 씰이 설치된다. 래버린스 씰은 이 둘을 기계적으로 격리시킴으로써 주추력 및 측추력을 보다 정확하게 측정할 수 있도록 돕는다. 하지만 덕트 내부 공급공기에 높은 수직 온도구배가 발생할 경우, 래버린스 씰의 격리가 파괴되어버린다. 본 논문에서는 이러한 접촉 문제를 해결하기 위한 노력의 일환으로 래버린스 씰 온도 제어장치를 제작/설치하였다. 본 장치를 실제 항공용 엔진시험에 적용한 결과, 높은 수직 온도구배가 생성되어도 래버린스 씰의 격리가 잘 유지되는 것을 확인할 수 있었다.

가스터빈 압축기용 허니컴 래버린스 실의 실제 운전조건에 따른 누설량 특성 분석 (HONEYCOMB LABYRINTH SEAL LEAKAGE CHARACTERISTIC ANALYSIS WITH ACTUAL OPERATING CONDITIONS ON THE COMPRESSOR OF GAS TURBINE)

  • 임샛별;김민규;강율호;박원규
    • 한국전산유체공학회지
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    • 제20권4호
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    • pp.102-108
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    • 2015
  • Recently, There are many studies in progress in order to improve the efficiency of the gas turbine. Leakage in losses of the gas turbine account for the largest proportion. Seal is a sealing device to reduce the flow from leaking by the pressure difference inside the turbine. Compressor has another value according to the shape and pressure conditions in each stage. Thus, it is necessary to seal design for boundary conditions in order to minimize leakage. At the actual operating conditions of the compressor, numerical analysis of honeycomb labyrinth seal was performed in accordance with pressure, temperature, rotor speed for CFD. As a result, when the temperature increases, the leakage is decreased. Also, when the pressure increases linearly with increased leakage, and there was no effect of the rotation speed.

도금액의 내부 유입 방지를 위한 래버린스 시일 설계 (Labyrinth Seal Design for Preventing Internal Inflow of Plating Solution)

  • 이덕규;김완두
    • Tribology and Lubricants
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    • 제33권6호
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    • pp.256-262
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    • 2017
  • Molten zinc plating is a process in which zinc is thinly coated over a metallic or non-metallic surface. It is used in various industrial fields for corrosion resistance and decoration. During the process, a steel sheet is passed through a roll that rotates inside the molten zinc liquid in the temperature range of $460^{\circ}C$ to $680^{\circ}C$, and the plating liquid flows into the roll causing abrasion and erosion of the roll surface. This problem is known to accelerate the replacement cycle of the roll and cause considerable economic loss owing to production line stoppage. Here, we propose a mechanism that operates at high temperature and pressure with a labyrinth type seal design to resolve this problem. We theoretically investigate the flow of the plating solution inside the seal and compute the minimum rotation speed required to prevent the plating solution from entering the seal chamber. In addition, we calculate the thermal deformation of the seal during operation and display thermally deformed dimensions at high temperatures. To verify the theoretical results, we perform experiments using pilot test equipment working in the actual plating environment. The experimental results are in good agreement with theoretical results. We expect our results to contribute towards the extension of the roll's life span and thereby reduce the economic losses.

Investigation on helix type labyrinth seal to minimize leakage flow of cryogen for rotating superconducting machines

  • Yubin Kim;Kihwan Kim;Seungcheol Ryu;Hojun Cha;Seokho Kim
    • 한국초전도ㆍ저온공학회논문지
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    • 제26권1호
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    • pp.25-30
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    • 2024
  • High-temperature superconducting rotors offer advantages in terms of output-to-weight ratio and efficiency compared to conventional phase conduction motors or generators. The rotor can be cooled by conduction cooling, which attaches a cryocooler, and by refrigerant circulation, which uses circulating liquid or gas neon, helium and hydrogen. Recent work has focused on environmental issues and on high-temperature superconducting motors cooled with liquid hydrogen that can be combined with fuel cells. However, to ensure smooth supply and return of the cryogenic cooling fluid, a cryogenic rotational coupling between the rotating and stationary parts is necessary. Additionally, the development of a sealing structure to minimize fluid leakage applicable to the coupling is essential. This study describes the design and performance evaluation of a non-contact sealing method, specifically a labyrinth seal, which avoids power loss and heat load caused by friction in contact sealing structures. The seal design incorporates a spiral flow path to reduce leakage using centrifugal force, and computational fluid dynamics (CFD) simulations were conducted to analyze the flow path and rotational speed. A performance evaluation device was configured and employed to evaluate the designed seal. The results of this study will be used to develop a cryogenic rotational coupling with supply and return flow paths for cryogenic applications.

An Experimental Study on Sealing Improvements of Non-Contact Type Seal for Oil Mist Lubrication

  • Na, Byung-Chul;Chun, Keyoung-Jin;Han, Dong-Chul
    • KSTLE International Journal
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    • 제3권2호
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    • pp.79-83
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    • 2002
  • Sealing an oil-air mixture plays important roles to have an enhanced lubrication for high speed spindle. High speed spindle requires non-contact type of sealing mechanism. Current work emphases on the investigation of the air jet effect on the protective collar type labyrinth seal. To improve the sealing capability of conventional labyrinth seal, air jet was injected against through the leakage flow, It has a combined geometry of a protective collar type and an air jet type. Both of a numerical analysis by CFD (Computational Fluid Dynamics) and experimental measurements are carried out to verify sealing improvement The sealing effects of the leakage clearance and the air jet magnitude are studied in various parameters. The results of pressure drop in the experiment match reasonably to those of the simulation by introducing a flow coefficient Effect of sealing improvement is explained as decreasing of leakage clearance by air jetting. Thus, sealing effect is improved by amount of air jetting even though clearance becomes larger.

대형 발전용 스팀터빈 다이아프램 시일의 성능 및 유동특성 해석 (Performance and Flow Characteristics Analyses of Diaphragm Seals for Large Power-Generation Steam Turbines)

  • 박준영;이안성;김병옥;김영철
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회B
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    • pp.2612-2615
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    • 2008
  • Diaphragm seals have great effects on the performance of large power-generation steam turbines. Hence, it is important to decrease the leakage flow through the diaphragm seals and understand the flow characteristics within the diaphragm seals. In this study, numerical analysis was carried-out with the seals of large one-body type diaphragms developed by a domestic company. CFX, which is a commercial CFD code, was used to analyze the performance and flow characteristics of the diaphragm seals for three difference clearance cases. The results of numerical analysis show variations in the performance and flow characteristics according to the changes of labyrinth seal clearance.

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고속주축용 라비린스 시일의 형상설계에 관한 연구 (A study on Geometry of Labyrinth Seal for High Speed Machining Center)

  • 나병철;전경진;한동철
    • Tribology and Lubricants
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    • 제13권3호
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    • pp.56-62
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    • 1997
  • Sealing an oil-air mixture plays important roles to have an enhanced lubrication for high speed spindle. High speed spindles require non-contact type sealing mechanism. In this study, an optimum seal design to minimize leakage is concerned in the aspect of flow control. This paper categorizes geometries of mostly used non-contact type seals and analyzes each leakage characteristics to minimize a leakage on sealing area. Effect of minimum clearance and its position are considered according to variation of detail geometry. The estimation of non-leaking property is determined by amount of pressure drop in the leakage path assuming constant leakage flow. To simulate an oil jet or oil mist type high speed spindle lubrication, the working fluid is regarded as two phases that are mixed flow of oil phase and air phase. Both of the turbulence and the compressible flow model were introduced in CFD(Computational Fluid Dynamics) analysis. Design parameters has been induced to minimize leakage in limited space, and a methodological study on geometrical optimization has been conducted.

3차원 CFD를 사용한 환상 실의 누설량 예측 (Prediction of Annular Type Seal Leakage Using 3D CFD)

  • 석희수;하태웅
    • Tribology and Lubricants
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    • 제25권3호
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    • pp.150-156
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    • 2009
  • Precise leakage prediction for annular type seals of turbomachinery is necessary for enhancing their efficiency and various prediction methods have been developed. As the seal passage is designed intricately, the analysis based on Bulk-flow concept which has been mainly used in predicting seal leakage is limited. In order to improve the seal leakage prediction, full Navier-Stokes Equations with turbulent model derived in the seal flow passage have to be solved. In this study, 3D CFD (Computational Fluid Dynamics) analysis has been performed for predicting leakage of various non-contact type anular seals using FLUENT. Compared to the results by Bulk-flow model analysis, experiment, and 2D CFD analysis, the result of 3D CFD analysis shows improvement in predicting seal leakage, especially for the parallel grooved pump seal.

역방향스월자기주입 시일의 누설 성능에 관한 실험 연구 (Test Results of Leakage Performance for Anti-Swirl Self-Injection Seals)

  • 김창호;이용복
    • Tribology and Lubricants
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    • 제7권2호
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    • pp.41-45
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    • 1991
  • An experimental investigation for leakage performance of five anti-swirl self-injection seals was carried out to select an optimum configuration for minimum leakage. Test results show that the self-injection mechanism with a plain seal generally degrades the leakage performance of noncontacting seals; however, through a series of the test program, an optimum anti-swirl self injection seal was selected to obtain a comparable leakage performance with a damper seal. A 12 holes anti-swirl and anti-leakage self-injected. configuration with a labyrinth surface gives minimum leakage among the tested anti-swirl self-injection seals.