Experimental Investigation of the Flow Field in a Multistage Axial Flow Compressor

The nature of the flow field in a three stage axial flow compressor, including a detailed survey at the exit of an embedded stator as well as the overall performance of the compressor is presented and interpreted in this paper. The measurements include area traverse of a miniature five hole probe (1.07 mm dia) downstream of stator 2, radial traverses of a miniature five hole probe at the inlet, downstream of stator 3 and at the exit of the compressor at various circumferential locations, area traverse of a low response thermocouple probe downstream of stator 2, radial traverses of a single sensor hot-wire probe at the inlet, and casing static pressure measurements at various circumferential and axial locations across the compressor at the peak efficiency operating point. Mean velocity, pressure and total temperature contours as well as secondary flow contours at the exit of the stator 2 are reported and interpreted. Secondary flow contours show the migration of fluid particles toward the core of the low pressure regions located near the suction side casing endwall corner.

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Experimental Investigation of the Flow Field in a Multistage Axial Flow Compressor

Volume 1: Turbomachinery ◽

10.1115/94-gt-455 ◽

1994 ◽

Cited By ~ 4

Author(s):

B. Lakshminarayana ◽

N. Suryavamshl ◽

J. Prato ◽

R. Moritz

Keyword(s):

Flow Field ◽

Secondary Flow ◽

Axial Flow ◽

Suction Side ◽

Temporal Variations ◽

Hot Wire ◽

Suction Surface ◽

Mean Velocity ◽

Axial Flow Compressor ◽

Flow Compressor

The nature of the flow field in a three stage axial flow compressor, including a detailed survey at the exit of an embedded stator as well as the overall performance of the compressor is presented and interpreted in this paper. The measurements include area traverse of a miniature five hole probe (1.07 mm dia) downstream of stator 2, radial traverses of a miniature five hole probe at the inlet, downstream of stator 3 and at the exit of the compressor at various circumferential locations, area traverse of a low response thermocouple probe downstream of stator 2, radial traverses of a single sensor hot-wire probe at the inlet, and casing static pressure measurements at various circumferential and axial locations across the compressor at the peak efficiency operating point. Spectral analysis of the hot-wire data reveal the existence of several harmonics of all three rotor blade passing frequencies at the inlet of the compressor. Mean velocity, pressure and total temperature contours as well as secondary flow contours at the exit of the stator 2 are reported and interpreted. Hub clearance flow is shown to eliminate the suction surface corner separation. Secondary flow contours show the migration of fluid particles toward the core of the low pressure regions located near the suction side casing endwall corner. The RMS value of the spatial fluctuations in mean velocity downstream of the second stator (which appear as temporal variations to the subsequent rotor) have been derived and shown to be significant.

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Mean Velocity and Decay Characteristics of the Guidevane and Stator Blade Wake of an Axial Flow Compressor

Journal of Engineering for Power ◽

10.1115/1.3230231 ◽

1980 ◽

Vol 102 (1) ◽

pp. 50-60 ◽

Cited By ~ 23

Author(s):

B. Lakshminarayana ◽

R. Davino

Keyword(s):

Axial Flow ◽

Mean Velocity ◽

Axial Flow Compressor ◽

Profile Similarity ◽

Blade Row ◽

Wake Production ◽

Flow Curvature ◽

Stator Blade ◽

Single Sensor ◽

Flow Compressor

Pure tone noise, blade row vibrations, and aerodynamic losses are phenomena which are influenced by stator and IGV blade wake production, decay, and interaction in an axial-flow compressor. The objective of this investigation is to develop a better understanding of the nature of stator and IGV blade wakes that are influenced by the presence of centrifugal forces due to flow curvature. A single sensor hot wire probe was employed to determine the three mean velocity components of stator and IGV wakes of a single stage compressor. These wake profiles indicated a varying decay rate of the tangential and axial wake velocity components and a wake profile similarity. An analysis, which predicts this trend, has been developed. The radial velocities are found to be appreciable in both IGV and the stator wakes. This wake data as well as the data from other sources are correlated in this paper. Appreciable static pressure gradient across the wake is found to exist near the trailing edge of both stator and IGV.

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Aspirating Probe Measurements of the Unsteady Total Temperature Field Downstream of an Embedded Stator in a Multistage Axial Flow Compressor

Volume 1: Turbomachinery ◽

10.1115/96-gt-543 ◽

1996 ◽

Cited By ~ 3

Author(s):

N. Suryavamshi ◽

B. Lakshminarayana ◽

J. Prato

Keyword(s):

Axial Flow ◽

Pressure Data ◽

Peak Efficiency ◽

Axial Flow Compressor ◽

Composite Flow ◽

Total Temperature ◽

Temperature And Pressure ◽

Flow Compressor ◽

Isentropic Efficiency ◽

Probe Measurements

The results from the area traverse measurements of the unsteady total temperature using a high response aspirating probe downstream of the second stator of a three stage axial flow compressor are presented. The measurements were conducted at the peak efficiency operating point. The unsteady total temperature data is resolved into deterministic and unresolved components. Hub and casing regions have high levels of unsteadiness and consequently high levels of mixing. These regions have significant levels of shaft resolved and unresolved unsteadiness. Comparisons are made between the total temperature and the total pressure data to examine the rotor 2 wake characteristics and the temporal variation of the stator exit flow. Isentropic efficiency calculations at the midpitch location show that there is about a 4% change in the algebraically averaged efficiency across the blades of the second rotor and if all the rotor 2 blades were behaving as a “best” blade, the improvement in efficiency would be about 1.3%. An attempt is made to create a composite flow field picture by correlating the unsteady velocity data with temperature and pressure data.

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Effects of Endwall Profiling on Axial Flow Compressor Stage

Volume 7: Turbomachinery, Parts A and B ◽

10.1115/gt2009-59418 ◽

2009 ◽

Cited By ~ 4

Author(s):

Jialing Lu ◽

Wuli Chu ◽

Yanhui Wu

Keyword(s):

Flow Field ◽

Engineering Design ◽

Axial Flow ◽

Design Tool ◽

Operating Conditions ◽

Compressor Stage ◽

Corner Separation ◽

Axial Flow Compressor ◽

Flow Compressor ◽

Stage Efficiency

In recent years endwall profiling has been well validated as a major new engineering design tool for the reduction of secondary loss in turbines. However, its application on compressors have been rarely performed and reported. This paper documents the findings of the analysis for diminishing compressor stator corner separation using endwall profiling; In the study, novel profiled endwalls were designed and numerically studied on a subsonic axial-flow compressor stage. The compressor stator endwalls were profiled on both axial and azimuthal directions. The results showed, the stator corner separation was significantly suppressed under all the operating conditions by implementing this profiled endwall. Significant improvements on stage pressure ratios and stage efficiency were observed. Detailed flow field changes, as well as endwall profiling methods are provided in the paper, so that the results of this research can be referenced to other compressor designs.

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