누설유량과 회전체동역학적 성능을 고려한 래버린스 씰 설계
Labyrinth Seal Design considering Leakage Flow Rate andRotordynamic Performance
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초록
This study proposes a procedure for designing a labyrinth seal that meets both leakage flow rate and rotordynamic performance criteria (effective damping, amplification factor, separation margin, logarithmic decrement, and vibration amplitude). The seal is modeled using a one control volume (1CV) bulk flow approach to predict the leakage flow rate and rotordynamic coefficients. The rotating shaft is modeled with the finite element (FE) method and is assumed to be supported by two linearized bearings. Geometry, material and operating conditions of the rotating shaft, and the supporting characteristics of the bearings were fixed. A single labyrinth seal is placed at the center of the rotor, and the linearized dynamic coefficients predicted by the seal numerical model are inserted as linear springs and dampers at the seal position. Seal designs that satisfy both leakage and rotordynamic performance are searched by modifying five seal design parameters using the multi-grid method. The five design parameters include pre-swirl ratio, number of teeth, tooth pitch, tooth height and tooth tip width. In total, 12500 seal models are examined and the optimal seal design is selected. Finally, normalization was performed to select the optimal labyrinth seal designs that satisfy the system performance requirements.
Abstract
This study proposes a procedure for designing a labyrinth seal that meets both leakage flow rate and rotordynamic performance criteria (effective damping, amplification factor, separation margin, logarithmic decrement, and vibration amplitude). The seal is modeled using a one control volume (1CV) bulk flow approach to predict the leakage flow rate and rotordynamic coefficients. The rotating shaft is modeled with the finite element (FE) method and is assumed to be supported by two linearized bearings. Geometry, material and operating conditions of the rotating shaft, and the supporting characteristics of the bearings were fixed. A single labyrinth seal is placed at the center of the rotor, and the linearized dynamic coefficients predicted by the seal numerical model are inserted as linear springs and dampers at the seal position. Seal designs that satisfy both leakage and rotordynamic performance are searched by modifying five seal design parameters using the multi-grid method. The five design parameters include pre-swirl ratio, number of teeth, tooth pitch, tooth height and tooth tip width. In total, 12500 seal models are examined and the optimal seal design is selected. Finally, normalization was performed to select the optimal labyrinth seal designs that satisfy the system performance requirements.
참고문헌 (20)
- Vance, J. M., "Machinery Vibration and Rotordynamics" (2010), Wiley
- Eldin, A. M. G., "Leakage and rotordynamic effects of pocket damper seals and see-through labyrinth seals", Doctor, pp.2007
- Fang, X., "New correlations of single-phase friction factor for turbulent pipe flow and evaluation of existing single-phase friction factor correlations", Nuclear Engineering and Design, 241(3), pp.897~902 (2011)
- Predictions vs. Test Results for Leakage and Rotordynamic Force Coefficients of a Fully Partitioned Pocket Damper Seal and a Labyrinth Seal-Limitations of the Current Computational Model, "Shan, W.", Research Consortium, Texas A&M University, ~ (2013)
- Li, Z., "Labyrinth seal rotordynamic characteristics part I : Operational conditions effects", Journal of Propulsion and Power, 32(5), pp.1199~1211 (2016)
- Li, Z., "Labyrinth seal rotordynamic characteristics part II : Geometrical parameter effects", Journal of Propulsion and Power, 32(5), pp.1281~1291 (2016)
- Childs, D. W., "A n Iwatsubo Based Solution for Labyrinth Seals : A Compariso n to Experimental Results", ASME Journal of Engineering for Gas Turbines and Power, 108, pp.325~331 (1986)
- Cangioli, F., "On the Thermodynamic Process in the Bulk-Flow Model for the Estimation of the Dynamic Coefficients of Labyrinth Seals", Journal of Engineering for Gas Turbines and Power, 140(3) (2018)
- Scharrer, J. K., "Theory Versus Experiment for the Rotordynamic Coefficients of Labyrinth Gas Seals : Part I-A Two Control Volume Model", ASME. J. Vib., Acoust., Stress, and Reliab, 110(3), pp.270~280 (1988)
- Pelletti, J., "A Comparison of Experimental Results and Theoretical Predictions for the Rotordynamic Coefficients of Short(LID = 1", 6)Labyrinth Seals, 1991, ~
- Ha, T. W., "Rotordynamic Analysis of a Labyrinth Seal Using the Moody's Friction-Factor Model", KSFM Journal of Fluid Machinery, 2(3), pp.52~58 (1999)
- 하태웅, "스팀 터빈용 조합형 엇갈린 래버린스 실의 누설량 및 동특성 해석", 한국유체기계학회 논문집, 7(6), pp.45~54 (2004), 한국유체기계학회
- Omar M. Sahor, "Cavity pressures, velocity and leakage computation in straight through or stepped labyrinth seals", M.S, pp.1994
- Numann K., "Zur Frage der Verwendung von Durchblickdichtungen im Dampfturbinenbau", Maschinenbautechnik, 13(4), pp.188~195 (1964)
- Wang, T., "Rotordynamic Characteristics of the Straight-Through Labyrinth Seal Based on the Applicability Analysis of Leakage Models Using Bulk-Flow Method", Journal of Engineering for Gas Turbines and Power, 144(1) (2022)
- 이정인, "스월 브레이크가 장착된 래버린스 씰의 동특성 해석", 한국트라이볼로지학회지, 38(2), pp.63~69 (2022), 한국트라이볼로지학회
- 김병옥, "API 617 규격에 의거한 프로세스 가스 터보압축기의 로터다이나믹 해석 및 안정성 검토", 한국유체기계학회 논문집, 12(5), pp.47~53 (2009), 한국유체기계학회
- Zhang, E., "Dynamic Behavior Analysis of a Rotor System Based on a Nonlinear Labyrinth-Seal Forces Model", Journal of Computational and Nonlinear Dynamics, 13(10) (2018)
- Zhang, W., "Improving the rotordynamic stability of short labyrinth seals using positive preswirl", Journal of Vibroengineering, 22(6), pp.1295~1308 (2020)
- "Standard API 684., API Standard Paragraphs Rotordynamic Tutorial: Lateral Critical Speeds, Unbalance Response, Stability, Train Torsionals, and Rotor Balancing", ~ (2005)