Skip to main content
SpringerLink
Log in

Rotordynamic characteristics of a novel pocket damper seal with self-regulated injection

  • Original Article
  • Published:
Journal of Mechanical Science and Technology Aims and scope Submit manuscript

Abstract

The conventional fully partitioned pocket damper seal (FPDS) was improved by introducing several nozzles on the first seal tooth, which generates a reverse injection fluid suppressing the cavity flow in the circumferential direction. Computational fluid dynamics (CFD) models of the conventional FPDS and current novel FPDS were established. An infinitesimal theory was employed to identify the rotordynamic coefficient of the FPDS. The influence of nozzle types (negative, straight, positive), inlet/outlet areas, deflection angles (θ) on the rotordynamic performance was comprehensively analyzed. It was found that reducing the circumferential flow in the first seal cavity is crucial for increasing the stability of the FPDS. A negative nozzle angle can restrict the circumferential flow effectively and significantly improve the effective damping and system stability. The crossover frequency for the novel FPDS with θ = −10° is ∼62 Hz, which is much lower than that for the conventional FPDS (∼85 Hz). The increasing inlet/outlet area ratio of the nozzle can also enhance the seal stability. Increasing the negative nozzle angle (θ = none, −10°, −15°, −20°) can effectively increase the effective damping and reduce the crossover frequency from ∼85 Hz to ∼38 Hz. However, the novel FPDS with three kinds of nozzles shows a slight increase (< 2.5 %) in the leakage flow rate compared with the conventional FPDS.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Abbreviations

a :

Major axis of the elliptical orbit (m)

b :

Minor axis of the elliptical orbit (m)

C ee, C αα :

Direct damping in e, a direction (N·s/m)

C eα, C αe :

Cross-coupled damping in e, a direction (N·s/m)

C xx, C yy :

Direct damping in x, y direction (N·s/m)

C xy, C yx :

Cross-coupled damping in x, y direction (N·s/m)

C :

Average direct damping (N·s/m)

C eff :

Effective damping (N·s/m)

C r :

Seal clearance (mm)

d :

Rotor diameter (mm)

F e, F α :

Seal reaction force in e, α direction (N)

F e0, F α0 :

Static seal reaction force in e, α direction (N)

h :

Pocket height (mm)

K ee, K αα :

Direct stiffness in e, α direction (N/m)

K eα, K αe :

Cross-coupled stiffness in e, α direction (N/m)

K xx, K yy :

Direct stiffness in x, y direction (N/m)

K xy, K yx :

Cross-coupled stiffness in x, y direction (N/m)

K :

Average direct stiffness (N/m)

k :

Average cross-coupled stiffness (N/m)

l :

Seal length (mm)

P in :

Supply pressure (bar)

P out :

Discharge pressure (bar)

t :

Rib thickness (mm)

W 1, W 2 :

Pocket width (mm)

ω :

Rotational speed (r/min)

Ω:

Whirling frequency (Hz)

PS:

Inlet preswirl velocity (m/s)

θ :

Deflection angle the nozzles (deg)

γ :

Inlet/outlet area ratio of the nozzle

References

  1. R. E. Chupp, R. C. Hendricks, S. B. Lattime and B. M. Steinetz, Sealing in turbomachinery, J. of Propulsion and Power, 22(2) (2006) 313–349.

    Article  Google Scholar 

  2. D. W. Childs, Turbomachinery Rotordynamics: Phenomena, Modeling, and Analysis, John Wiley & Sons, New York (1993).

    Google Scholar 

  3. J. M. Vance and R. R. Shultz, A new damper seal for turbomachinery, Proceedings of the 14th Biennial ASME Conference on Vibration and Noise, Albuquerque, NM (1993) 139–148.

  4. J. M. Vance and J. M. Li, Test results of a new damper seal for vibration reduction in turbomachinery, ASME J. of Engineering for Gas Turbines and Power, 118(4) (1996) 843–846.

    Article  Google Scholar 

  5. D. Ransom, J. M. Li, L. San Andrés and J. M. Vance, Experimental force coefficients for a two-bladed labyrinth seal and a four-pocket damper seal, ASME J. of Tribology, 121(2) (1999) 370–376.

    Article  Google Scholar 

  6. J. M. Li, R. Aguilar, R. L. San Andrés and J. M. Vance, Dynamic force coefficients of a multiple-blade, multiple-pocket gas damper seal: test results and predictions, ASME J. of Tribology, 122(1) (2000) 317–322.

    Article  Google Scholar 

  7. J. M. Vance, A. Sharma and N. Jayakar, Effect of frequency and design parameters on pocket damper seal performance, Proceedings of IMECE2002, ASME International Mechanical Engineering Congress & Exposition, New Orleans, Louisiana (2002) 799–807.

  8. B. H. Ertas, A. M. Gamal and J. M. Vance, Rotordynamic force coefficients of pocket damper seals, ASME J. of Turbomachinery, 128(4) (2006) 725–737.

    Article  Google Scholar 

  9. B. H. Ertas and J. M. Vance, The influence of same-sign cross-coupled stiffness on rotordynamics, ASME J. of Vibration and Acoustics, 129(1) (2007) 24–31.

    Article  Google Scholar 

  10. A. M. Gamal, Leakage and rotordynamic effects of pocket damper seals and see-through labyrinth seals, Ph.D. Thesis, Texas A&M University, Texas (2007).

  11. A. M. Gamal, B. H. Ertas and J. M. Vance, High-pressure pocket damper seals: leakage rates and cavity pressures, ASME J. of Turbomachinery, 129(4) (2007) 826–834.

    Article  Google Scholar 

  12. J. M. Li, F. Kushner and P. DeChoudhury, Experimental evaluation of slotted pocket gas damper seals on a rotating test rig, The 47th International Gas Turbine & Aeroengine Technical Congress, Exposition & User Symposium, Amsterdam, The Netherlands (2002) 1125–1138.

  13. B. H. Ertas, Rotordynamic force coefficients of pocket damper seals, Ph.D. Thesis, Texas A&M University, Texas (2005).

  14. B. H. Ertas, A. Delgado and G. Vannini, Rotordynamic force coefficients for three types of annular gas seals with inlet preswirl and high differential pressure ratio, ASME J. of Engineering for Gas Turbines and Power, 134(4) (2012) 042503.

    Article  Google Scholar 

  15. C. Griebel, Impact analysis of pocket damper seal geometry variations on leakage performance and rotordynamic force coefficients using computational fluid dynamics, ASME J. of Engineering for Gas Turbines and Power, 141(4) (2019) 041024.

    Article  Google Scholar 

  16. Z. G. Li, J. Li and Z. P. Feng, Numerical investigations on the leakage and rotordynamic characteristics of pocket damper seals: part I. Effects of pressure ratio, rotational speed, and inlet preswirl, ASME J. of Engineering for Gas Turbines and Power, 137(3) (2015) 032503.

    Article  Google Scholar 

  17. Z. G. Li, J. Li and Z. P. Feng, Numerical investigations on the leakage and rotordynamic characteristics of pocket damper seals: part II: effects of partition wall type, partition wall number, and cavity depth, ASME J. of Engineering for Gas Turbines and Power, 137(3) (2015) 032504.

    Article  Google Scholar 

  18. J. M. Li, L. San Andrés and J. M. Vance, A bulk-flow analysis of multiple-pocket gas damper seals, ASME J. of Engineering for Gas Turbines and Power, 121(2) (1999) 355–363.

    Article  Google Scholar 

  19. F. Cangioli, G. Vannini and T. Chirathadam, A novel bulk-flow model for pocket damper seals, Proceedings of ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition, Phoenix, Arizona, USA (2019) V07BT34A002.

  20. J. M. Li, D. Ransom, L. San Andrés and J. M. Vance, Comparison of predictions with test results for rotordynamic coefficients of a four-pocket gas damper seal, ASME J. of Tribology, 121(2) (1999) 363–369.

    Article  Google Scholar 

  21. J. Yang, L. San Andrés and X. Lu, Leakage and dynamic force coefficients of a pocket damper seal operating under a wet gas condition: tests vs. predictions, Proceedings of ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition, Phoenix, Arizona, USA (2019) V07BT34A011.

  22. Z. G. Li, J. Li and Z. P. Feng, Numerical investigation on the leakage and static stability characteristics of pocket damper seals at high eccentricity ratios, Proceedings of ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition, Charlotte, NC, USA (2017) V05BT15A010.

  23. Z. G. Li, J. Li and Z. P. Feng, Investigations on the rotordynamic coefficients of pocket damper seals using the multifrequency, one-dimensional, whirling orbit model and RANS solutions, ASME J. of Engineering for Gas Turbines and Power, 134(10) (2012) 102510.

    Article  Google Scholar 

  24. Z. G. Li, J. Li and Z. P. Feng, Numerical comparison of rotordynamic characteristics for a fully partitioned pocket damper seal and a labyrinth seal with high positive and negative inlet preswirl, ASME J. of Engineering for Gas Turbines and Power, 138(4) (2016) 042505.

    Article  Google Scholar 

  25. H. Benckert and J. Wachter, Flow induced spring coefficients of labyrinth seals for application in rotor dynamics, NASA Conference Publication 2133: Rotordynamic Instability Problems in High-Performance Turbomachinery, Texas A&M University, College Station (1980) 189–212.

    Google Scholar 

  26. G. Kirk, Labyrinth seal analysis for centrifugal compressor design — theory and practice, Proceedings of the Second IFToMM International Conference, Tokyo, Japan (1986) 14–17.

  27. E. A. Memmott, Tilt pad seal and damper bearing applications to high speed and high-density centrifugal compressor, Proceedings of Third IFToMM International Conference, Lyon, France (1990) 585–590.

  28. E. A. Soto and D. W. Childs, Experimental rotordynamic coefficient results for (a) a labyrinth seal with and without shunt injection and (b) a honeycomb seal, ASME J. of Engineering for Gas Turbines and Power, 121(1) (1999) 153–159.

    Article  Google Scholar 

  29. D. W. Childs, J. E. Mclean, M. Zhang and S. P. Arthur, Rotordynamic performance of a negative-swirl brake for a tooth-on-stator labyrinth seal, ASME J. of Engineering for Gas Turbines and Power, 138(6) (2016) 062505.

    Article  Google Scholar 

  30. A. Untaroiu, H. Jin, G. Fu, V. Hayrapetiau and K. Elebiary, The effects of fluid preswirl and swirl brakes design on the performance of labyrinth seals, ASME J. of Engineering for Gas Turbines and Power, 140(8) (2018) 082503.

    Article  Google Scholar 

  31. W. F. Zhang, Q. L. Gu, J. G. Yang and C. Li, Application of a novel rotordynamic identification method for annular seals with arbitrary elliptical orbits and eccentricities, ASME J. of Engineering for Gas Turbines and Power, 141(9) (2019) 091016.

    Article  Google Scholar 

  32. ANSYS CFX-Solver Theory Guide, Release 11.0, ANSYS, Inc., Canonsburg, Pennsylvania (2006).

Download references

Acknowledgments

This work was supported by the National Natural Science Foundation of China [51875361], Natural Science Foundation of Shanghai [20ZR1439200].

Author information

Authors and Affiliations

  1. School of Energy and Power Engineering, University of Shanghai for Science and Technology, 516 Jungong Road, Shanghai, 200093, China

    Wanfu Zhang, Pengbo Qin, Lu Yin & Chun Li

  2. North China Electric Power Research Institute Co., Ltd., 1 Dizang’an South Lane, Beijing, 100045, China

    Xiaobin Zhang

  3. Envision Energy Co., Ltd., 1065 Zhongshan West Road, Shanghai, 200050, China

    Kai Ma

Authors
  1. Wanfu Zhang
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Pengbo Qin
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Xiaobin Zhang
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Kai Ma
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Lu Yin
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Chun Li
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Wanfu Zhang.

Additional information

Wanfu Zhang received the Ph.D. from the Southeast University, Nanjing, China in 2013. He has been working at University of Shanghai for Science Technology, Shanghai, China since 2014. He was a visiting scholar at Turbomachinery Laboratory of Texas A&M University during Nov. 2018-Nov. 2019. His current research interests include rotordynamics, static and dynamic performance of annular seals, vibration of turbomachinery.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Zhang, W., Qin, P., Zhang, X. et al. Rotordynamic characteristics of a novel pocket damper seal with self-regulated injection. J Mech Sci Technol 35, 3421–3434 (2021). https://doi.org/10.1007/s12206-021-0715-9

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12206-021-0715-9

Keywords

Search

Navigation