0
Research Papers

Numerical Simulation of Stall Inception Mechanisms in a Centrifugal Compressor With Vaned Diffuser

[+] Author and Article Information
Y. Bousquet

ISAE,
Université de Toulouse,
10 Avenue Edouard Belin BP 54032,
Cedex 4,
Toulouse 31055, France
e-mail: Yannick.Bousquet@isae.fr

N. Binder

ISAE,
Université de Toulouse,
10 Avenue Edouard Belin BP 54032,
Cedex 4,
Toulouse 31055, France
e-mail: Nicolas.Binder@isae.fr

G. Dufour

ISAE,
Université de Toulouse,
10 Avenue Edouard Belin BP 54032,
Cedex 4,
Toulouse 31055, France
e-mail: Guillaume.Dufour@isae.fr

X. Carbonneau

ISAE,
Université de Toulouse,
10 Avenue Edouard Belin BP 54032,
Cedex 4,
Toulouse 31055, France
e-mail: Xavier.Carbonneau@isae.fr

M. Roumeas

Liebherr-Aerospace Toulouse SAS,
408 Avenue des Etats Unis,
Toulouse 31016, France
e-mail: Mathieu.Roumeas@liebherr.fr

I. Trebinjac

Laboratoire de Mécanique des,
Fluides et d'Acoustique,
UMR CNRS 5509 Ecole Centrale de Lyon,
UCB Lyon 1,
INSA,
36 Avenue Guy de Collongue,
Ecully Cedex 69134, France

1Corresponding author.

Manuscript received November 16, 2015; final manuscript received May 20, 2016; published online June 14, 2016. Assoc. Editor: Ricardo F. Martinez-Botas.

J. Turbomach 138(12), 121005 (Jun 14, 2016) (9 pages) Paper No: TURBO-15-1263; doi: 10.1115/1.4033704 History: Received November 16, 2015; Revised May 20, 2016

The present paper numerically investigates the stall inception mechanisms in a centrifugal compressor stage composed of a splittered unshrouded impeller and a vaned diffuser. Unsteady numerical simulations have been conducted on a calculation domain comprising all the blade passages over 360 deg for the impeller and the diffuser. Three stable operating points are simulated along a speed line, and the full path to instability is investigated. The paper focusses first on the effects of the mass flow reduction on the flow topology at the inlet of both components. Then, a detailed analysis of stall inception mechanisms is proposed. It is shown that at the inlet of both components, the mass flow reduction induces boundary layer separation on the blade suction side, which results in a vortex tube having its upper end at the casing and its lower end at the blade wall. Some similarities with flows in axial compressor operating at stall condition are outlined. The stall inception process starts with the growth of the amplitude of a modal wave rotating in the vaneless space. As the flow in the compressor is subsonic, the wave propagates upstream and interacts with the impeller flow structure. This interaction leads to the drop in the impeller pressure ratio.

Copyright © 2016 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Three-dimensional sketch of the compressor stage

Grahic Jump Location
Fig. 2

Meridional view of the compressor stage

Grahic Jump Location
Fig. 3

Pressure ratio of the compressor stage

Grahic Jump Location
Fig. 4

Line integral convolution of the skin-friction pattern on the impeller blade suction side

Grahic Jump Location
Fig. 5

Illustration of flow mechanism in the blade tip region (left) and contour of time-averaged reduced meridional velocity at section B for OP3 operating point (right)

Grahic Jump Location
Fig. 6

Isosurface of positive axial velocity (blue), isosurface of negative axial velocity (red), and isosurface of λ2 vortex criteria (golden) for the operating point OP3

Grahic Jump Location
Fig. 7

Time-averaged axisymmetric profile of the incidence angle at the diffuser inlet from hub (h* = 0) to shroud (h* = 1)

Grahic Jump Location
Fig. 8

Contour of time-averaged reduced radial velocity at 90% span at the diffuser inlet (left) and isosurface of the λ2 vortex criteria (right) for the operating point OP3

Grahic Jump Location
Fig. 9

Amplitude of the spatial modes for the operating point OP1 (top) and for the operating point OP3 (bottom)

Grahic Jump Location
Fig. 10

Evolution of the mass flow at the inlet and at the outlet of the calculation domain during the stall onset simulation. The throttle condition is modified at t = 0 rev.

Grahic Jump Location
Fig. 11

Evolution of the total-to-static pressure ratio during the stall onset. The throttle condition is modified at t = 0 rev.

Grahic Jump Location
Fig. 12

Pressure signals during the stall onset extracted at shroud in the vaneless space. The throttle condition is modified at t = 0 rev.

Grahic Jump Location
Fig. 13

Amplitude of the spatial mode extracted in the vaneless space at shroud. The throttle condition is modified at t = 0 rev.

Grahic Jump Location
Fig. 14

Amplitude of the spatial mode mθ=1. The throttle condition is modified at t = 0 rev.

Grahic Jump Location
Fig. 15

Contour of instantaneous static pressure at 98% span at t = −2 rev (left); isosurface of instantaneous density at t = −2 rev (middle and right)

Grahic Jump Location
Fig. 16

Contour of instantaneous entropy at 98% span at t = −2 rev

Grahic Jump Location
Fig. 17

Contour of instantaneous static pressure at the shroud and at the impeller inlet

Grahic Jump Location
Fig. 18

Pressure signals during the stall onset extracted at the shroud at the impeller inlet. The throttle condition is modified at t = 0 rev.

Grahic Jump Location
Fig. 19

Evolution of the total-to-total pressure ratio of the impeller during the stall transient. The throttle condition is modified at t = 0 rev.

Tables

Errata

Discussions

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