Laser Anemometer Measurements in a Transonic Axial Flow Compressor Rotor

A laser anemometer system employing an efficient data acquisition technique has been used to make measurements upstream, within, and downstream of the compressor rotor. A fluorescent dye technique allowed measurements within endwall boundary layers. Adjustable laser beam orientation minimized shadowed regions and enabled radial velocity measurements outside of the blade row. The flow phenomena investigated include flow variations from passage to passage, the rotor shock system, three-dimensional flows in the blade wake, and the development of the outer endwall boundary layer. Laser anemometer measurements are compared to a numerical solution of the streamfunction equations and to measurements made with conventional instrumentation.

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Efficient Laser Anemometer for Intra-Rotor Flow Mapping in Turbomachinery

Journal of Engineering for Power ◽

10.1115/1.3230737 ◽

1981 ◽

Vol 103 (2) ◽

pp. 424-429 ◽

Cited By ~ 14

Author(s):

J. A. Powell ◽

A. J. Strazisar ◽

R. G. Seasholtz

Keyword(s):

Axial Flow ◽

Flow Mapping ◽

Graphic Display ◽

Flow Measurements ◽

Compressor Rotor ◽

Seed Particles ◽

Laser Anemometer ◽

Efficient Data ◽

Flow Compressor ◽

Data Acquisition Process

Innovative features of the anemometer include: (1) a rapid and efficient data acquisition process, (2) a detailed real-time graphic display of the data being accumulated, and (3) input laser beam positioning that maximizes the size of the intra-rotor region being mapped. Results are presented that demonstrate the anemometer’s capability in flow mapping within a transonic axial-flow compressor rotor. Typically, a velocity profile, derived from 30,000 measurements along 1000 sequential circumferential positions covering 20 blade passages, can be obtained in 30 s. The use of fluorescent seed particles allows flow measurements near the rotor hub and the casing window.

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A New Approach to the Experimental Study of Turbomachinery Flow Phenomena

Journal of Engineering for Power ◽

10.1115/1.3446259 ◽

1977 ◽

Vol 99 (1) ◽

pp. 97-105 ◽

Cited By ~ 20

Author(s):

J. P. Gostelow

Keyword(s):

Flow Field ◽

Unsteady Flow ◽

Axial Flow ◽

Centrifugal Pumps ◽

New Approach ◽

Static Pressure Distribution ◽

Compressor Rotor ◽

Flow Phenomena ◽

On Line ◽

Flow Compressor

Measurements of the unsteady flow field over a rotor and within its wake are needed in the development of most turbomachines. The technique advocated is that of data acquisition by on-line computer, using the periodic passing of a blade as a phase reference. The phase-lock averaging process is described as is its use in reducing the noise of raw data traces. Measurements of the unsteady flow over a cascade and of the resulting boundary layer behavior are presented. The approach was used in interpreting the unsteady flow field of an axial-flow compressor rotor and the static pressure distribution over the rotor tip. Finally the application to centrifugal pumps is discussed, enabling the designer to obtain information on the suction pressures and the extent of any separated region.

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G607 Unsteady Three Dimensional Flow Behavior of Separated Flow in an Axial Flow Compressor Rotor at Rotating Stall(1)

The Proceedings of the Fluids engineering conference ◽

10.1299/jsmefed.2006._g607-a_ ◽

2006 ◽

Vol 2006 (0) ◽

pp. _G607-a_

Author(s):

Ken-ichiro IWAKIRI ◽

Ryusuke OHTAGURO ◽

Sho BONKOHARA ◽

Yasuhiro SHIBAMOTO ◽

Kazutoyo YAMADA ◽

...

Keyword(s):

Flow Behavior ◽

Three Dimensional ◽

Axial Flow ◽

Separated Flow ◽

Rotating Stall ◽

Three Dimensional Flow ◽

Axial Flow Compressor ◽

Dimensional Flow ◽

Compressor Rotor ◽

Flow Compressor

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Numerical Prediction of Wakes in Cascades and Compressor Rotors Including the Effects of Mixing: Part II — Rotor Passage Flow and Wakes Including the Effects of Spanwise Mixing

Volume 1: Turbomachinery ◽

10.1115/91-gt-222 ◽

1991 ◽

Author(s):

N. Suryavamshi ◽

B. Lakshminarayana

Keyword(s):

Flow Field ◽

Three Dimensional ◽

Axial Flow ◽

Radial Component ◽

Navier Stokes ◽

Mean Velocity ◽

Compressor Rotor ◽

Entire Flow ◽

High Reynolds ◽

Flow Compressor

The results of a numerical investigation to predict the flow field including wakes and mixing in axial flow compressor rotors has been presented in this paper. The wake behaviour in a moderately loaded compressor rotor has been studied numerically using a three-dimensional incompressible Navier-Stokes solver with a high Reynolds number form of the k–ε turbulence model. The equations are solved using a time dependent implicit technique. The agreement between the measured data and the predictions are good; including the blade boundary layer profiles, wake mean velocity profiles and decay. The ability of the pseudo-compressibility scheme to predict the entire flow field including the near and far wake profiles and its decay characteristics, effect of loading and the viscous losses of a three-dimensional rotor flow field has been demonstrated. An analysis of the passage averaged velocities and the pressure coefficients shows that the mixing in the downstream regions away from the hub and annulus walls is dominated by wake diffusion. In regions away from the walls, the radial mixing is predominantly caused by the transport of mass, momentum and energy by the radial component of velocity in the wake.

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Numerical Prediction of Wakes in Cascades and Compressor Rotors Including the Effects of Mixing: Part II—Rotor Passage Flow and Wakes Including the Effects of Spanwise Mixing

Journal of Turbomachinery ◽

10.1115/1.2929186 ◽

1992 ◽

Vol 114 (3) ◽

pp. 617-626 ◽

Cited By ~ 3

Author(s):

N. Suryavamshi ◽

B. Lakshminarayana

Keyword(s):

Flow Field ◽

Three Dimensional ◽

Axial Flow ◽

Radial Component ◽

Navier Stokes ◽

Mean Velocity ◽

Compressor Rotor ◽

Entire Flow ◽

High Reynolds ◽

Flow Compressor

The results of a numerical investigation to predict the flow field including wakes and mixing in axial flow compressor rotors has been presented in this paper. The wake behavior in a moderately loaded compressor rotor has been studied numerically using a three-dimensional incompressible Navier–Stokes solver with a high Reynolds number form of the k–ε turbulence model. The equations are solved using a time-dependent implicit technique. The agreement between the measured data and the predictions is good, including the blade boundary layer profiles, wake mean velocity profiles, and decay. The ability of the pseudocompressibility scheme to predict the entire flow field including the near and far wake profiles and its decay characteristics, effect of loading, and the viscous losses of a three-dimensional rotor flow field has been demonstrated. An analysis of the passage-averaged velocities and the pressure coefficients shows that the mixing in the downstream regions away from the hub and annulus walls is dominated by wake diffusion. In regions away from the walls, the radial mixing is predominantly caused by the transport of mass, momentum, and energy by the radial component of velocity in the wake.

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Analysis of Three-Dimensional Viscous Flow in a Supersonic Axial Flow Compressor Rotor With Emphasis on Tip Leakage Flow

Volume 1: Turbomachinery ◽

10.1115/92-gt-388 ◽

1992 ◽

Cited By ~ 3

Author(s):

G. Perrin ◽

F. Leboeuf ◽

W. N. Dawes

Keyword(s):

Stokes Equations ◽

Three Dimensional ◽

Axial Flow ◽

Leakage Flow ◽

Tip Leakage Flow ◽

Axial Velocity Component ◽

Tip Leakage ◽

Axial Flow Compressor ◽

Compressor Rotor ◽

Flow Compressor

A three-dimensional computation has been performed for a supersonic axial flow compressor rotor by solving the Navier-Stokes equations. The results of the computation are used to analyse the tip leakage flow in more detail. As well as the global behaviour of the tip leakage vortex, the analysis focuses on the origins of this vortex. It is shown that the main source of its vorticity is the shear layer at the tip of the blade associated with the shedding of the blade loading. A separation occurs, with respect to the axial velocity component, as the jet leakage flow, crossing the clearance gap, encounters the upstream incoming flow. Although the entropy increase of this separation is low, it has a strong effect on the mixing around the leakage vortex. Overall, for this compressor and the choosen operating point, the tip leakage effects are localised near the tip wall and suction side of the blade.

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An Experimental Study of the Compressor Rotor Blade Boundary Layer

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.3239731 ◽

1985 ◽

Vol 107 (2) ◽

pp. 364-372 ◽

Cited By ~ 3

Author(s):

M. Pouagare ◽

J. M. Galmes ◽

B. Lakshminarayana

Keyword(s):

Boundary Layer ◽

Rotor Blade ◽

Radial Profile ◽

Three Dimensional ◽

Axial Flow ◽

Tip Leakage Flow ◽

Wall Boundary Layer ◽

Compressor Rotor ◽

Blade Tip ◽

Flow Compressor

The three-dimensional turbulent boundary layer developing on a rotor blade of an axial flow compressor was measured using a minature “x” configuration hot-wire probe. The measurements were carried out at nine radial locations on both surfaces of the blade at various chordwise locations. The data derived includes streamwise and radial mean velocities and turbulence intensities. The validity of conventional velocity profiles such as the “power law profile” for the streamwise profile, and Mager and Eichelbrenner’s for the radial profile, is examined. A modification to Mager’s crossflow profile is proposed. Away from the blade tip, the streamwise component of the blade boundary layer seems to be mainly influenced by the streamwise pressure gradient. Near the tip of the blade, the behavior of the blade boundary layer is affected by the tip leakage flow and the annulus wall boundary layer. The “tangential blockage” due to the blade boundary layer is derived from the data. The profile losses are found to be less than that of an equivalent cascade, except in the tip region of the blade.

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