0
Research Papers: Flows in Complex Systems

Numerical Investigation on Labyrinth Seal Leakage Flow and Its Effects on Aerodynamic Performance for a Multistage Centrifugal Compressor

[+] Author and Article Information
Bing Qiao

School of Energy and Power Engineering,
Xi'an Jiaotong University,
Xi'an, Shaanxi 710049, China
e-mail: qiaobingq@stu.xjtu.edu.cn

Yaping Ju

School of Energy and Power Engineering,
Xi'an Jiaotong University,
Xi'an, Shaanxi 710049, China
e-mail: yapingju@mail.xjtu.edu.cn

Chuhua Zhang

State Key Laboratory for Strength and Vibration
of Mechanical Structures,
School of Energy and Power Engineering,
Xi'an Jiaotong University,
Xi'an, Shaanxi 710049, China
e-mail: chzhang@mail.xjtu.edu.cn

1Corresponding author.

Contributed by the Fluids Engineering Division of ASME for publication in the JOURNAL OF FLUIDS ENGINEERING. Manuscript received June 10, 2018; final manuscript received December 9, 2018; published online January 23, 2019. Assoc. Editor: Hui Hu.

J. Fluids Eng 141(7), 071107 (Jan 23, 2019) (12 pages) Paper No: FE-18-1403; doi: 10.1115/1.4042370 History: Received June 10, 2018; Revised December 09, 2018

Labyrinth seals are widely used in industrial centrifugal compressors to reduce leakage. However, no work has been conducted to numerically investigate the detailed seal leakage flow and its effects in an environment of multistage centrifugal compressor. To clarify the flow mechanism of leakage flow and the interaction mechanism between leakage and mainstream flow in multistage centrifugal compressors, the flow of the last two stages from a four-stage centrifugal compressor is studied using computational fluid dynamics (CFD) model with and without considerations of labyrinth seal leakage paths, i.e., two shroud seals, one interstage seal, and one balance piston seal. The results show that the leakage flow in shroud and hub cavities can be described as a Batchelor-type flow. The Ekman number of the cavity Batchelor flow is small and corresponds to thin boundary layers while the Rossby number is at unity order implying the importance of rotating effects. The leakage flow through the shroud, interstage, and balance piston labyrinth seals is decreased by the combined effects of throttling and diffusion flow, and has distinctive flow structures associated with the type of labyrinth seal. The influence of leakage flow on the mainstream flow can be described by suction or injection mode. The suction mode is beneficial to the improvement of mainstream flow quality while the injection mode is harmful. This work is of scientific significance to enrich the knowledge of internal fluid mechanics and of potential application value to control and design the leakage flow in real configurations of multistage centrifugal compressors.

Copyright © 2019 by ASME
Your Session has timed out. Please sign back in to continue.

References

Pinto, R. N. , Afzal, A. , D'Souza, L. V. , Ansari, Z. , and Samee, A. D. M. , 2017, “ Computational Fluid Dynamics in Turbomachinery: A Review of State of the Art,” Arch. Comput. Methods Eng., 24(3), pp. 467–479. [CrossRef]
Halawa, T. , Gadala, M. S. , Alqaradawi, M. , and Badr, O. , 2016, “ Influence of Changing Casing Groove Parameters on the Performance of Centrifugal Compressors Near Stall Condition,” ASME J. Fluids Eng., 138(2), p. 021104. [CrossRef]
Chen, H. , 2017, “ Component Matching of Centrifugal Compressors for Turbocharger Application,” ASME Paper No. GT 2017-63108.
Stuart, C. , Spence, S. , Filsinger, D. , Starke, A. , and Kim, S. I. , 2018, “ Characterizing the Influence of Impeller Exit Recirculation on Centrifugal Compressor Work Input,” ASME J. Turbomach., 140(1), p. 011005. [CrossRef]
Moore, J. J. , 2003, “ Three-Dimensional CFD Rotordynamic Analysis of Gas Labyrinth Seals,” ASME J. Vib. Acoust., 125(4), pp. 427–433. [CrossRef]
Hirano, T. , Guo, Z. , and Kirk, R. G. , 2005, “ Application of Computational Fluid Dynamics Analysis for Rotating Machinery—Part II: Labyrinth Seal Analysis,” ASME J. Eng. Gas Turbines Power, 127(4), pp. 820–826. [CrossRef]
Eldin, A. M. G. , 2007, “ Leakage and Rotordynamic Effects of Pocket Damper Seals and See-Through Labyrinth Seals,” Ph.D. thesis, Texas A&M University, College Station, TX. http://oaktrust.library.tamu.edu/handle/1969.1/ETD-TAMU-2084?show=full
Li, Z. G. , Li, J. , and Feng, Z. P. , 2016, “ Labyrinth Seal Rotordynamic Characteristics—Part II: Geometrical Parameter Effects,” AIAA J. Propul. Power, 32(5), pp. 1281–1291. [CrossRef]
Cangioli, F. , Pennacchi, P. , Vannini, G. , Ciuchicchi, L. , Vania, A. , Chatterton, S. , and Dang, P. V. , 2017, “ On the Thermodynamic Process in the Bulk-Flow Model for the Estimation of the Dynamic Coefficients of Labyrinth Seals,” ASME J. Eng. Gas Turbines Power, 140(3), p. 032502. [CrossRef]
Guidotti, E. , Naldi, G. , Tapinassi, L. , and Chockalingam, V. , 2012, “ Cavity Flow Modeling in an Industrial Centrifugal Compressor Stage at Design and Off-Design Conditions,” ASME Paper No. GT 2012-68288.
Satish, K. V. V. N. K. , Guidotti, E. , Rubino, D. T. , Tapinassi, L. , and Prasad, S. , 2013, “ Accuracy of Centrifugal Compressor Stages Performance Prediction by Means of High Fidelity CFD and Validation Using Advanced Aerodynamic Probe,” ASME Paper No. GT 2013-95618.
Hildebrandt, A. , and Schilling, F. , 2017, “ Numerical and Experimental Investigation of Return Channel Vane Aerodynamics With Two-Dimensional and Three-Dimensional Vanes,” ASME J. Turbomach., 139(1), p. 011010. [CrossRef]
Mischo, B. , Ribi, B. , Seebass-Linggi, C. , and Mauri, S. , 2009, “ Influence of Labyrinth Seal Leakage on Centrifugal Compressor Performance,” ASME Paper No. GT2009-59524.
Weber, A. , Morsbach, C. , Kügeler, E. , Rube, C. , and Wedeking, M. , 2016, “ Flow Analysis of a High Flow Rate Centrifugal Compressor Stage and Comparison With Test Rig Data,” ASME Paper No. GT2016-56551.
Sun, Z. G. , Tan, C. Q. , and Zhang, D. Y. , 2009, “ Flow Field Structures of the Impeller Backside Cavity and Its Influences on the Centrifugal Compressor,” ASME Paper No. GT2009-59879.
Kaluza, P. , Landgraf, C. , Schwarz, P. , Jeschke, P. , and Smythe, C. , 2017, “ On the Influence of a Hubside Exducer Cavity and Bleed Air in a Close-Coupled Centrifugal Compressor Stage,” ASME J. Turbomach., 139(7), p. 071011. [CrossRef]
Wang, Z. H. , and Xi, G. , 2011, “ Influences of Cavity Leakage on the Design of Low Flow Coefficient Centrifugal Impeller,” Sci. China Technol. Sci., 54(2), pp. 311–317. [CrossRef]
Marechale, R. , Ji, M. , and Cave, M. , 2015, “ Experimental and Numerical Investigation of Labyrinth Seal Clearance Impact on Centrifugal Impeller Performance,” ASME Paper No. GT2015-43778.
Munk, D. J. , Kipouros, T. , Vio, G. A. , Parks, G. T. , and Steven, G. P. , 2018, “ Multiobjective and Multi-Physics Topology Optimization Using an Updated Smart Normal Constraint Bi-Directional Evolutionary Structural Optimization Method,” Struct. Multidiscip. Optim., 57(2), pp. 665–688. [CrossRef]
Yan, H. , Liu, Y. W. , Li, Q. S. , and Lu, L. P. , 2018, “ Turbulence Characteristics in Corner Separation in a Highly Loaded Linear Compressor Cascade,” Aerosp. Sci. Technol., 75, pp. 139–154. [CrossRef]
Serre, E. , Del Arco, E. C. , and Bontoux, P. , 2001, “ Annular and Spiral Patterns in Flows Between Rotating and Stationary Discs,” J. Fluid Mech., 434, pp. 65–100. [CrossRef]
Poncet, S. , Schiestel, R. , and Chauve, M. P. , 2005, “ Centrifugal Flow in a Rotor-Stator Cavity,” ASME J. Fluids Eng., 127(4), pp. 787–794. [CrossRef]
Liu, G. , Du, Q. , Liu, J. , Wang, P. , and Zhu, J. Q. , 2016, “ Numerical Investigation of Radial Inflow in the Impeller Rear Cavity With and Without Baffle,” Sci. China Technol. Sci., 59(3), pp. 456–467. [CrossRef]
Wang, C. Z. , Tang, F. , Li, Q. , and Wang, X. H. , 2018, “ Experimental Investigation of the Microscale Rotor–Stator Cavity Flow With Rotating Superhydrophobic Surface,” Exp. Fluids, 59(3), p. 47. [CrossRef]
Batchelor, G. K. , 1951, “ Note on a Class of Solutions of the Navier-Stokes Equations Representing Steady Rotationally-Symmetric Flow,” Q. J. Mech. Appl. Math., 4(1), pp. 29–41. [CrossRef]
Bödewadt, U. T. , 1940, “ Die Drehströmung über festem Grunde,” Z. Angew. Math. Mech., 20(5), pp. 241–253. [CrossRef]
Ekman, V. W. , 1905, “ On the Influence of the Earth's Rotation on Ocean-Currents,” Ark. Mat. Astron. Fys., 2(11), pp. 1–52. https://jscholarship.library.jhu.edu/handle/1774.2/33989
Childs, P. R. N. , 2011, Rotating Flow, Butterworth-Heinemann, Oxford, UK.
Wang, B. , Okamoto, K. , Yamaguchi, K. , and Teramoto, S. , 2014, “ Loss Mechanisms in Shear-Force Pump With Multiple Corotating Disks,” ASME J. Fluids Eng., 136(8), p. 081101. [CrossRef]
Greitzer, E. M. , Tan, C. S. , and Graf, M. B. , 2004, Internal Flow: Concepts and Applications, Cambridge University Press, New York.
Owen, J. M. , 1989, “ An Approximate Solution for the Flow Between a Rotating and a Stationary Disk,” ASME J. Turbomach., 111(3), pp. 323–332. [CrossRef]
Itoh, M. , Yamada, Y. , Imao, S. , and Gonda, M. , 1992, “ Experiments on Turbulent Flow Due to an Enclosed Rotating Disk,” Exp. Therm. Fluid Sci., 5(3), pp. 359–368. [CrossRef]
Debuchy, R. , Nour, F. A. , and Bois, G. , 2010, “ An Analytical Modeling of the Central Core Flow in a Rotor-Stator System With Several Preswirl Conditions,” ASME J. Fluids Eng., 132(6), p. 061102. [CrossRef]
Özkan, M. , Thomas, P. J. , Cooper, A. J. , and Garrett, S. J. , 2017, “ Comparison of the Effects of Surface Roughness and Confinement on Rotor–Stator Cavity Flow,” Eng. Appl. Comput. Fluid Mech., 11(1), pp. 142–158.
Gantar, M. , Florjancic, D. , and Sirok, B. , 2002, “ Hydraulic Axial Thrust in Multistage Pumps—Origins and Solutions,” ASME J. Fluids Eng., 124(2), pp. 336–341. [CrossRef]
Gad-el-Hak, M. , and Bushnell, D. M. , 1991, “ Separation Control: Review,” ASME J. Fluids Eng., 113(1), pp. 5–30. [CrossRef]
Atik, H. , and van Dommelen, L. , 2008, “ Autogenous Suction to Prevent Laminar Boundary-Layer Separation,” ASME J. Fluids Eng., 130(1), p. 011201. [CrossRef]
Chinyoka, T. , 2011, “ Suction-Injection Control of Shear Banding in Non-Isothermal and Exothermic Channel Flow of Johnson-Segalman Liquids,” ASME J. Fluids Eng., 133(7), p. 071205. [CrossRef]
Keerthi, M. C. , Kushari, A. , and Somasundaram, V. , 2017, “ Experimental Study of Suction Flow Control Effectiveness in a Serpentine Intake,” ASME J. Fluids Eng., 139(10), p. 101104. [CrossRef]
Ju, Y. P. , Zhang, C. H. , and Chi, X. L. , 2012, “ Optimization of Centrifugal Impellers for Uniform Discharge Flow and Wide Operating Range,” AIAA J. Propul. Power, 28(5), pp. 888–899. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Geometry of the multistage centrifugal compressor

Grahic Jump Location
Fig. 2

Labyrinth seal geometry: (a) shroud seal, (b) interstage seal, and (c) balance piston seal

Grahic Jump Location
Fig. 3

Computational mesh

Grahic Jump Location
Fig. 4

Total pressure and total temperature distributions at the inlet of the last two stages of the four-stage centrifugal compressor: (a) total pressure and (b) total temperature

Grahic Jump Location
Fig. 5

The centrifugal compressor outlet total pressure

Grahic Jump Location
Fig. 6

Aerodynamic performance curves of the compressor with and without seal leakage

Grahic Jump Location
Fig. 7

Circumferentially averaged static pressure and flow velocity components in the first-stage shroud cavity: (a) static pressure and streamlines, (b) Vr, and (c) Vθ

Grahic Jump Location
Fig. 8

Circumferentially averaged static pressure and flow velocity components in the last-stage shroud cavity: (a) static pressure and streamlines, (b) Vr, and (c) Vθ

Grahic Jump Location
Fig. 9

Circumferentially averaged static pressure and flow velocity components in the first-stage hub cavity: (a) static pressure and streamlines, (b) Vr, and (c) Vθ

Grahic Jump Location
Fig. 10

Circumferentially averaged static pressure and flow velocity components in the last-stage hub cavity: (a) static pressure and streamlines, (b) Vr, and (c) Vθ

Grahic Jump Location
Fig. 11

Static pressure contours and streamlines in the first-stage shroud seal

Grahic Jump Location
Fig. 12

Static pressure contours and streamlines in the interstage seal

Grahic Jump Location
Fig. 13

Static pressure contours and streamlines in the balance piston seal

Grahic Jump Location
Fig. 14

Circumferentially average total pressure distributions and meridional streamlines of compressor: (a) without leakage and (b) with leakage

Grahic Jump Location
Fig. 15

Meridional streamline distributions in the compressor without partial seals: (a) without the first-stage shroud seal, (b) without the interstage seal, (c) without the last-stage shroud seal, and (d) without the balance piston seal

Grahic Jump Location
Fig. 16

Velocity vectors near the interfaces between the impeller outlets and leakage paths: (a) shroud-side interface in the first stage, (b) hub-side interface in the first stage, (c) shroud-side interface in the last stage, and (d) hub-side interface in the last stage

Tables

Errata

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In