Research Papers

A Numerical Investigation of Rotating Instability in Steam Turbine Last Stage

[+] Author and Article Information
L. Y. Zhang

e-mail: luying.zhang@eng.ox.ac.uk

L. He

e-mail: li.he@eng.ox.ac.uk
Department of Engineering Science,
University of Oxford,
Oxford, OX1 2JD, UK

H. Stüer

Fossil Power Generation,
Steam, Energy Sector,
Turbine Technology,
Siemens AD,
45478 Mülheim an der Ruhr, Germany

Contributed by the International Gas Turbine Institute (IGTI) of ASME for publication in the JOURNAL OF TURBOMACHINERY. Manuscript received June 24, 2011; final manuscript received August 16, 2011; published online October 22, 2012. Editor: David Wisler.

J. Turbomach 135(1), 011009 (Oct 22, 2012) (9 pages) Paper No: TURBO-11-1092; doi: 10.1115/1.4006330 History: Received June 24, 2011; Revised August 16, 2011

The unsteady flow phenomenon (identified as rotating instability) in the last stage of a low-pressure model steam turbine operated at very low mass flow conditions is numerically studied. This kind of instability has been observed previously in compressors and can be linked to the high structural stress levels associated with flow-induced blade vibrations. The overall objective of the study is to enhance the understanding of the rotating instability in steam turbines at off design conditions. A numerical analysis using a validated unsteady nonlinear time-domain CFD solver is performed. The 3D solution captures the massively separated flow structure in the rotor-exhaust region and the pressure ratio characteristics around the rotor tip of the test model turbine stage in good comparison with the experiment. A computational study with a multi-passage whole annulus domain on two different 2D blade sections is subsequently carried out. The computational results clearly show that a rotating instability in a turbine blading configuration can be captured by the 2D model. The frequency and spatial modal characteristics are analyzed. The simulations seem to be able to predict a rotating fluid dynamic instability with the similar characteristic features to those of the experiment. In contrast to many previous observations, the results for the present configurations suggest that the onset and development of rotating instabilities can occur without 3D and tip-leakage flows, although a quantitative comparison with the experimental data can only be expected to be possible with fully 3D unsteady solutions.

© 2013 by ASME
Your Session has timed out. Please sign back in to continue.


Day, I. J., 1993, “Stall Inception in Axial Flow Compressors,” ASME J. Turbomach., 115(1), pp. 1–9. [CrossRef]
He, L., 1997, “Computational Study of Rotating Stall Inception in Axial Compressors,” AIAA J. Propul. Power, 13(1), pp. 31–38. [CrossRef]
Hah, C., Schulze, R., Wagner, S., and Hennecke, D. K., 1999, “Numerical and Experimental Study for the Short Wavelength Stall Inception in a Low-Speed Axial Compressor,” Proceedings of the Fourteenth ISABE Conference, Florence, Italy, September 5–10, ISABE Paper No. 99-7033.
He, L., and Ismael, J. O., 1999, “Computations of Blade Row Stall Inception in Transonic Flows,” Aeronaut. J., 103(1025), pp. 317–324.
Bent, P. H., McLaughlin, D. K., and Thompson, D. E., 1992, “The Influence of Discharge Configuration on the Generation of Broadband Noise in Centrifugal Turbomachinery,” D. DGLR/AIAA Paper No. 92-02-099.
Mongeau, L., and Quinlan, D. A., 1992, “An Experimental Study of Broadband Noise Sources in Small Axial Fans,” Proceedings of the International Symposium on Fan Noise INCE, Senlis, France.
Mongeau, L., Thompson, D. E., and McLaughlin, D. K., 1993, “Sound Generation by Rotating Stall in Centrifugal Turbomachines,” J. Sound Vib., 163(1), pp. 1–30. [CrossRef]
Cumpsty, N. A., 2004, Compressor Aerodynamics 2nd ed., Krieger Publishing Company, Malabar, FL.
Gerschütz, W., Casey, M., and Truckenmüller, F., 2005, “Experimental Investigations of Rotating Flow Instabilities in the Last Stage of a Low-Pressure Model Steam Turbine During Windage,” Proc. IMechE, Part A: J. Power Energy, 219, pp. 499–510. [CrossRef]
Hah, C., Voges, M., Mueller, M., and Schiffer, H. P., 2010, “Characteristics of Tip Clearance Flow Instability in a Transonic Compressor,” Proceedings of ASME Turbo Expo 2010: Power for Land, Sea and Air (GT2010), Glasgow, UK, June 14–18, ASME Paper No. GT2010-22101, pp. 63–74. [CrossRef]
März, J., Hah, C., and Neise, W., 2002, “An Experimental and Numerical Investigation into the Mechanisms of Rotating Instability,” ASME J. Turbomach., 124(3), pp. 367–374. [CrossRef]
Vo, H. D., 2010, “Role of Tip Clearance Flow in Rotating Instabilities and Nonsynchronous Vibrations,” J. Propul. Power, 26(3), pp. 556–561. [CrossRef]
Kameier, F., and Neise, W., 1997, “Rotating Blade Flow Instability as a Source of Noise in Axial Turbomachines,” J. Sound Vib., 203(5), pp. 833–853. [CrossRef]
Liu, J. M., Holste, F., and Neise, W., 1996, “On the Azimuthal Mode Structure of Rotating Blade Flow Instabilities in Axial Turbomachines,” AIAA Meeting Papers on Disc, A9630853, AIAA Paper No. 96-1741.
Baumgartner, M., Kameier, F., and Hourmouziadis, J., 1995, “Non-Engine Order Blade Vibration in a High Pressure Compressor,” Proceedings of the ISABE-Twelfth International Symposium on Airbreathing Engines, Melbourne, Australia, September 10-15.
Sparlart, P. R., and Allmaras, S. R., 1992, “A One-Equation Turbulence Model for Aerodynamic Flows,” AIAA Paper No. 92-0439.
Jameson, A., Schmidt, W., and Turkel, E., 1981, “Numerical Solutions of the Euler Equation by Finite Volume Method Using Runge-Kutta Time-Stepping Scheme,” AIAA Paper No. 81-1259.
He, L., 2000, “3-D Navier-Stokes Analysis of Rotor-Stator Interactions in Axial-Flow Turbines,” Proc. IMech. E, Part A, 214(1), pp. 13–22. [CrossRef]
He, L., 1998, “Unsteady Flow in Oscillating Turbine Cascades,” ASME J. Turbomach., 120(2), pp. 262–275. [CrossRef]
Truckenmüller, F., 2002, “Untersuchungen zur aerodynamisch induzierten Schwingungsanregung von Niederdruck- Laufschaufeln bei extremer Teillastt,” Ph.D. thesis, University of Stuttgart, Stuttgart, Germany.
Denton, J. D., 1992, “The Calculation of Three-Dimensional Viscous Flow Through Multistage Turbomachine,” ASME J. Turbomach., 114(1), pp. 18–26. [CrossRef]


Grahic Jump Location
Fig. 1

Frequency spectra of total pressure in axial gap of the last stage of a model turbine [9]

Grahic Jump Location
Fig. 2

Steady pressures compared with experiment [19] (inlet flow angle 20 deg, Reynolds number 220,000)

Grahic Jump Location
Fig. 3

Contours of steady total pressures

Grahic Jump Location
Fig. 4

Computational domain of the model turbine stage (2 stator passages, 3 rotor passages)

Grahic Jump Location
Fig. 5

Calculated streamlines in the model turbine stage

Grahic Jump Location
Fig. 6

Experimental flow patterns. (ϕr=0.22) [20].

Grahic Jump Location
Fig. 7

Calculated rotor tip pressure ratio compared with the measurement [20]. (P31 and P32 are taken from the locations shown in Fig. 5(b).)

Grahic Jump Location
Fig. 8

2D multipassage configurations

Grahic Jump Location
Fig. 9

Static pressure contour on 90% span section (nominal flow condition, 100%)

Grahic Jump Location
Fig. 10

Static pressure contours on 90% span section (relative flow rate: 71.2%)

Grahic Jump Location
Fig. 11

Frequency spectra (90% span section) of unsteady pressures (relative mass flow rate: 74.8%)

Grahic Jump Location
Fig. 12

Frequency spectra (90% span section) of unsteady pressures (relative mass flow rate: 72.7%)

Grahic Jump Location
Fig. 13

Frequency spectra (90% span section) of unsteady pressures (relative mass flow rate: 71.2%)

Grahic Jump Location
Fig. 14

Time traces of static pressures of 90% span section (relative mass flow rate: 65.6%)

Grahic Jump Location
Fig. 15

Frequency spectra from stator frame of reference (90% span, relative mass flow rate: 70.4%)

Grahic Jump Location
Fig. 16

Frequency spectra from rotor frame of reference (90% span, relative mass flow rate: 70.4%)

Grahic Jump Location
Fig. 17

Computational meshes (90% span) (left: original; right: refined)

Grahic Jump Location
Fig. 18

Frequency spectra (90% span) of unsteady pressures from two meshes (relative mass flow rate: 70.4%)

Grahic Jump Location
Fig. 19

Time traces of static pressures of 10% span section (relative mass flow rate: 14.7%)

Grahic Jump Location
Fig. 20

Frequency spectra (10% span section) of unsteady pressures (relative mass flow rate: 14.7%)

Grahic Jump Location
Fig. 21

Pressure contours on 10% span section (relative flow rate: 14.7%)

Grahic Jump Location
Fig. 22

Relative velocity vectors on 10% span section (relative flow rate: 14.7%)

Grahic Jump Location
Fig. 23

Rotor pressure ratios with mass flow rates (Pexit and Pinlet are taken from the locations shown in Fig. 8(a))




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