- Physical Review Journals
All JournalsPhysics Magazine
Access Provided by Xinjiang University

Physical Review Fluids

Export citation

Export citation

Choose format for download:

Download Citation
  • Access by Xinjiang University

Inertial waves in turbine rim seal flows

Feng Gao (高锋)*, John W. Chew†, and Olaf Marxen‡

  • Faculty of Engineering and Physical Sciences, University of Surrey, Guildford GU2 7XH, United Kingdom

  • *Corresponding author: f.gao@surrey.ac.uk
  • †j.chew@surrey.ac.uk
  • ‡o.marxen@surrey.ac.uk
PDF

Phys. Rev. Fluids 5, 024802 – Published 24 February, 2020

DOI: https://doi.org/10.1103/PhysRevFluids.5.024802

Abstract

Rotating fluids are well-known to be susceptible to waves. This has received much attention from the geophysics, oceanographic and atmospheric research communities. Inertial waves, which are driven by restoring forces, for example, the Coriolis force, have been detected in the research fields mentioned above. This paper investigates inertial waves in turbine rim seal flows in turbomachinery. These are associated with the large-scale unsteady flow structures having distinct frequencies, unrelated to the main annulus blading, identified in many experimental and numerical studies. These unsteady flow structures have been shown in some cases to reduce sealing effectiveness and are difficult to predict with conventional steady Reynolds-averaged Navier-Stokes (RANS) approaches. Improved understanding of the underlying flow mechanisms and how these could be controlled is needed to improve the efficiency and stability of gas turbines. This study presents large-eddy simulations for three rim seal configurations—chute, axial, and radial rim seals—representative of those used in gas turbines. Evidence of inertial waves is shown in the axial and chute seals, with characteristic wave frequencies limited within the threshold for inertial waves given by classic linear theory (i.e., |f*/frel|≤2) and instantaneous flow fields showing helical characteristics. The radial seal, which limits the radial fluid motion with the seal geometry, restricts the Coriolis force and suppresses the inertial wave.

View figure in article

Physics Subject Headings (PhySH)

Article Text

References (39)

  1. H. P. Greenspan, The Theory of Rotating Fluids (Cambridge University Press, Cambridge, 1968).
  2. C. D. Andereck, S. S. Liu, and H. L. Swinney, Flow regimes in a circular Couette system with independently rotating cylinders, J. Fluid Mech. 164, 155 (1986).
  3. P. Melchior and B. Ducarme, Detection of inertial gravity oscillations in the Earth's core with a superconducting gravimeter at Brussels, Phys. Earth Planet. Inter. 42, 129 (1986).
  4. K. D. Aldridge and L. I. Lumb, Inertial waves identified in the Earth's fluid outer core, Nature 325, 421 (1987).
  5. C. Sidi and J. Barat, Observational evidence of an inertial wind structure in the stratosphere, J. Geophys. Res.: Atmos. 91, 1209 (1986).
  6. C. Garrett and W. Munk, Internal waves in the ocean, Annu. Rev. Fluid Mech. 11, 339 (1979).
  7. M. H. Alford, J. A. MacKinnon, H. L. Simmons, and J. D. Nash, Near-inertial internal gravity waves in the ocean, Annu. Rev. Marine Sci. 8, 95 (2016).
  8. M. Rieutord and L. Valdettaro, Inertial waves in a rotating spherical shell, J. Fluid Mech. 341, 77 (1997).
  9. E. Yarom and E. Sharon, Experimental observation of steady inertial wave turbulence in deep rotating flows, Nat. Phys. 10, 510 (2014).
  10. J. M. Lopez and P. Gutierrez-Castillo, Three-dimensional instabilities and inertial waves in a rapidly rotating split-cylinder flow, J. Fluid Mech. 800, 666 (2016).
  11. J. W. Chew, F. Gao, and D. M. Palermo, Flow mechanisms in axial turbine rim sealing, Proc. Inst. Mech. Eng. Part C 233, 7637 (2019).
  12. B. V. Johnson, G. J. Mack, R. E. Paolillo, and W. A. Daniels, Turbine rim seal gas path flow ingestion mechanisms, in Proceedings of the 30th Joint Propulsion Conference and Exhibit (AIAA, Reston, Virginia, 1994), Paper No. 94-2073.
  13. J. A. Scobie, C. M. Sangan, J. M. Owen, and G. D. Lock, Review of ingress in gas turbines, J. Eng. Gas Turbines Power 138, 120801 (2016).
  14. J. Boudet, V. N. D. Autef, J. W. Chew, N. J. Hills, and O. Gentilhomme, Numerical simulation of rim seal flows in axial turbines, Aeronaut. J. 109, 373 (2005).
  15. J. T. M. Horwood, F. P. Hualca, J. A. Scobie, M. Wilson, C. M. Sangan, and G. D. Lock, Experimental and computational investigation of flow instabilities in turbine rim seals, J. Eng. Gas Turbines Power 141, 011028 (2019).
  16. C. Cao, J. W. Chew, P. R. Millington, and S. I. Hogg, Interaction of rim seal and annulus flows in an axial flow turbine, in Proceedings of the ASME Turbo Expo 2003, collocated with the 2003 International Joint Power Generation Conference (ASME Press, New York, 2003), Paper No. GT2003-38368.
  17. J. Boudet, N. J. Hills, and J. W. Chew, Numerical simulation of the flow interaction between turbine main annulus and disc cavities, in Proceedings of the ASME Turbo Expo 2006: Power for Land, Sea, and Air (ASME Press, New York, 2006), Paper No. GT2006-90307.
  18. T. S. D. O'Mahoney, N. J. Hills, J. W. Chew, and T. Scanlon, Large-eddy simulation of rim seal ingestion, Proc. Inst. Mech. Eng., Part C 225, 2881 (2011).
  19. F. Gao, J. W. Chew, P. F. Beard, D. Amirante, and N. J. Hills, Large-eddy simulation of unsteady turbine rim sealing flows, Int. J. Heat Fluid Flow 70, 160 (2018).
  20. M. Rabs, F.-K. Benra, H. J. Dohmen, and O. Schneider, Investigation of flow instabilities near the rim cavity of a 1.5 stage gas turbine, in Proceedings of the ASME Turbo Expo 2009: Power for Land, Sea, and Air (ASME Press, New York, 2009), Paper No. GT2009-59965.
  21. M. Chilla, H. Hodson, and D. Newman, Unsteady interaction between annulus and turbine rim seal flows, J. Turbomach. 135, 051024 (2013).
  22. S. S. Savov, N. R. Atkins, and S. Uchida, A comparison of single and double lip rim seal geometries, J. Eng. Gas Turbines Power 139, 112601 (2017).
  23. R. A. Berg, C. S. Tan, Z. Ding, G. Laskowski, P. Palafox, and R. Miorini, Experimental and analytical assessment of cavity modes in a gas turbine wheelspace, J. Eng. Gas Turbines Power 140, 062502 (2018).
  24. R. Jakoby, T. Zierer, K. Lindblad, J. Larsson, L. de Vito, D. E. Bohn, J. Funcke, and A. Decker, Numerical simulation of the unsteady flow field in an axial gas turbine rim seal configuration, in Proceedings of the ASME Turbo Expo 2004: Power for Land, Sea, and Air (ASME Press, New York, 2004), Paper No. GT2004-53829.
  25. T. O'Mahoney, N. Hills, and J. Chew, Sensitivity of LES results from turbine rim seals to changes in grid resolution and sector size, Progr. Aerospace Sci. 52, 48 (2012).
  26. A. Pogorelov, M. Meinke, and W. Schröder, Large-eddy simulation of the unsteady full 3D rim seal flow in a one-stage axial-flow turbine, Flow, Turb. Combust. 102, 189 (2019).
  27. P. F. Beard, F. Gao, K. S. Chana, and J. W. Chew, Unsteady flow phenomena in turbine rim seals, J. Eng. Gas Turbines Power 139, 032501 (2016).
  28. O. Gentilhomme, N. J. Hills, A. B. Turner, and J. W. Chew, Measurement and analysis of ingestion through a turbine rim seal, J. Turbomach. 125, 505 (2003).
  29. A. Bru Revert, P. F. Beard, D. M. Palermo, J. W. Chew, and S. Bottenheim (private communication).
  30. F. Gao, N. Poujol, J. W. Chew, and P. F. Beard, Advanced numerical simulation of turbine rim seal flows and consideration for RANS turbulence modelling, in Proceedings of ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition (ASME Press, New York, 2018), Paper No. GT2018-75116.
  31. L. Fang, Background scalar-level anisotropy caused by low-wave-number truncation in turbulent flows, Phys. Rev. E 95, 033102 (2017).
  32. H. M. Blackburn and S. J. Sherwin, Formulation of a Galerkin spectral element-Fourier method for three-dimensional incompressible flows in cylindrical geometries, J. Comput. Phys. 197, 759 (2004).
  33. G. E. Karniadakis, M. Israeli, and S. A. Orszag, High-order splitting methods for the incompressible Navier-Stokes equations, J. Comput. Phys. 97, 414 (1991).
  34. G. S. Karamanos and G. E. Karniadakis, A spectral vanishing viscosity method for large-eddy simulations, J. Comput. Phys. 163, 22 (2000).
  35. D. B. Pitz, O. Marxen, and J. W. Chew, Onset of convection induced by centrifugal buoyancy in a rotating cavity, J. Fluid Mech. 826, 484 (2017).
  36. D. B. Pitz, J. W. Chew, and O. Marxen, Large-eddy simulation of buoyancy-induced flow in a sealed rotating cavity, J. Eng. Gas Turbines Power 141, 021020 (2018).
  37. F. Gao, D. B. Pitz, and J. W. Chew, Numerical investigation of buoyancy-induced flow in a sealed rapidly rotating disc cavity, Int. J. Heat Mass Transf. 147, 118860 (2020).
  38. S. Galtier, Weak inertial-wave turbulence theory, Phys. Rev. E 68, 015301 (2003).
  39. Q. Chen, S. Chen, and G. L. Eyink, The joint cascade of energy and helicity in three-dimensional turbulence, Phys. Fluids 15, 361 (2003).

Outline

Information

Phys. Rev. Fluids 5, 024802– Published 24 February, 2020
  • Received 21 August 2019
  • Accepted 4 February 2020
Crossmark - Check for updates button

©2020 American Physical Society

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation