Stator Endwall Leading-Edge Sweep and Hub Shroud Influence on Compressor Performance

1986 ◽  
Vol 108 (2) ◽  
pp. 224-232 ◽  
Author(s):  
D. L. Tweedt ◽  
T. H. Okiishi ◽  
M. D. Hathaway
Keyword(s):  
Axial Flow ◽  
Leading Edge ◽  
Outer Diameter ◽  
Loss Reduction ◽  
Local Loss ◽  
Axial Flow Compressor ◽  
Stator Blade ◽  
Inner Diameter ◽  
Compressor Performance ◽  
Flow Compressor

The use of stator endwall leading-edge sweep to improve axial-flow compressor stator row performance was examined experimentally. The aerodynamics of three stator hub (inner diameter) conditions, namely, a running clearance, a stationary clearance, and a shroud, were also investigated. Leading-edge sweep in the endwall regions of a stator blade can be beneficial in terms of loss reduction on the casing (outer diameter) end of a stator blade. It can also help at the hub end of a stator blade when either a stationary hub clearance or a hub shroud is used. A leading-edge sweep is detrimental (local loss increase) on the hub end of a stator blade when a running hub clearance is used. A running clearance is aerodynamically preferable to a stationary clearance.

Stator Endwall Leading-Edge Sweep and Hub Shroud Influence on Compressor Performance

1986 ◽  
Author(s):  
D. L. Tweedt ◽  
T. H. Okiishi ◽  
M. D. Hathaway
Keyword(s):  
Axial Flow ◽  
Leading Edge ◽  
Outer Diameter ◽  
Loss Reduction ◽  
Local Loss ◽  
Axial Flow Compressor ◽  
Stator Blade ◽  
Inner Diameter ◽  
Compressor Performance ◽  
Flow Compressor

The use of stator endwall leading-edge sweep to improve axial-flow compressor stator row performance was examined experimentally. The aerodynamics of three stator hub (inner diameter) conditions, namely, a running clearance, a stationary clearance, and a shroud were also investigated. Leading-edge sweep in the endwall regions of a stator blade can be beneficial in terms of loss reduction on the casing (outer diameter) end of a stator blade. It can also help at the hub end of a stator blade when either a stationary hub clearance or a hub shroud is used. A leading-edge sweep is detrimental (local loss increase) on the hub end of a stator blade when a running hub clearance is used. A running clearance is aerodynamically preferable to a stationary clearance.

The Manufacture of Glass Cloth/Resin Blades for an Axial Flow Compressor

1954 ◽  
Vol 58 (522) ◽  
pp. 434-434
Author(s):  
J. H. Horlock
Keyword(s):  
Polyester Resin ◽  
Axial Flow ◽  
Glass Cloth ◽  
Axial Flow Compressor ◽  
Stator Blade ◽  
Flow Compressor ◽  
The University

Glass Cloth/Polyester resin laminates similar to those described by Irving and Saunders (Journal, February 1954) have been used at the University Engineering Laboratory, Cambridge, in the manufacture of blades for an axial flow compressor. In the first experiments, an existing aluminium stator blade was used as a pattern, and a mould was made by pouring molten type metal round this pattern, held in a steel sided moulding box.

Numerical Simulation of Steady Air Injection Flow Control Effects on a Transonic Axial Flow Compressor

2012 ◽  
Vol 224 ◽  
pp. 352-357
Author(s):  
Islem Benhegouga ◽  
Ce Yang
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Pressure Ratio ◽  
Axial Flow ◽  
Leading Edge ◽  
Air Injection ◽  
Axial Flow Compressor ◽  
Blade Tip ◽  
Flow Compressor

In this work, steady air injection upstream of the blade leading edge was used in a transonic axial flow compressor, NASA rotor 37. The injectors were placed at 27 % upstream of the axial chord length at blade tip, the injection mass flow rate is 3% of the chock mass flow rate, and 3 yaw angles were used, respectively -20°, -30°, and -40°. Negative yaw angles were measured relative to the compressor face in opposite direction of rotational speeds. To reveal the mechanism, steady numerical simulations were performed using FINE/TURBO software package. The results show that the stall mass flow can be decreased about 2.5 %, and an increase in the total pressure ratio up to 0.5%.

Detection of a Rotating Stall Precursor in Isolated Axial Flow Compressor Rotors

1991 ◽  
Vol 113 (2) ◽  
pp. 281-287 ◽  
Author(s):  
M. Inoue ◽  
M. Kuroumaru ◽  
T. Iwamoto ◽  
Y. Ando
Keyword(s):  
Pressure Sensor ◽  
Pressure Fluctuation ◽  
Axial Flow ◽  
Leading Edge ◽  
Rotating Stall ◽  
Statistical Characteristics ◽  
Flow Passage ◽  
Axial Flow Compressor ◽  
Flow Compressor ◽  
Stall Precursor

Statistical characteristics of pressure fluctuation on the casing wall of two axial flow compressor rotors have been investigated experimentally to find a precursor of rotating stall. Near stall, the casing wall pressure across a flow passage near the leading edge is characterized by a highly unsteady region where low-momentum fluid accumulates. The periodicity of the pressure fluctuation with blade spacing disappears and an alternative phenomenon comes into existence, which supports the disturbance propagating at a different speed from the rotor revolution. The precursor of rotating stall can be detected by monitoring collapse of the periodicity in the pressure fluctuation. To represent the periodicity qualitatively, a practical detection parameter has been proposed, which is easily obtained from signals of a single pressure sensor installed at an appropriate position on the casing wall during operation of a compressor.

New Profile Loss Model for Improved Prediction of Transonic Axial Flow Compressor Performance in Choking Region

2015 ◽  
Author(s):  
Sangjo Kim ◽  
Donghyun Kim ◽  
Kuisoon Kim ◽  
Changmin Son ◽  
Myungho Kim ◽  
...  
Keyword(s):  
Performance Prediction ◽  
Incidence Angle ◽  
Axial Flow ◽  
Operating Conditions ◽  
Loss Model ◽  
Axial Flow Compressor ◽  
Compressor Performance ◽  
Loss Models ◽  
Flow Compressor ◽  
Profile Loss

New off-design profile loss models have been developed by performing thorough investigations on compressor performance prediction using one-dimensional stage-stacking approach and three-dimensional computational flow dynamics (CFD) results. Generally, a loss model incorporating various compressor geometry and operating conditions is required to predict the performance of various types of compressors. In this study, three sets of selected loss models were applied to predict axial flow compressor performance using stage-stacking approach. The results were compared with experimental data as well as CFD results. The comparison shows an interesting observation in choking region where the existing loss models cannot capture the rapid decrease in pressure and efficiency while CFD predicted the characteristics. Therefore, an improved off-design profile loss model is proposed for better compressor performance prediction in choking region. The improved model was derived from the correlation between the normalized total loss and the incidence angle. The choking incidence angle, which is a major factor in determining the off-design profile loss, was derived from correlations between the inlet Mach number, throat width-to-inlet spacing ratio, and minimum loss incidence angle. The revised stage-stacking program employing new profile loss model together with a set of loss models was applied to predict a single and multistage compressors for comparison. The results confirmed that the new profile loss model can be widely used for predicting the performance of single and multistage compressor.

Effects of tip clearance size on the unsteady flow behaviors and performance in a counter-rotating axial flow compressor

2017 ◽  
Vol 233 (3) ◽  
pp. 1059-1070 ◽  
Author(s):  
Xiaochen Mao ◽  
Bo Liu ◽  
Hang Zhao
Keyword(s):  
Unsteady Flow ◽  
Incidence Angle ◽  
Axial Flow ◽  
Leading Edge ◽  
Tip Clearance ◽  
Leakage Flow ◽  
Tip Leakage Flow ◽  
Tip Leakage ◽  
Axial Flow Compressor ◽  
Flow Compressor

This paper presents the studies performed to better understand the effects of increased tip clearance size on the unsteady flow behaviors and overall performance under the rotor–rotor interaction environment in a counter-rotating axial flow compressor. The investigation method is based on the three-dimensional unsteady Reynolds-averaged Navier–Stokes simulations. The results show that the intensified tip leakage flow in front rotor (R1) caused by the increased tip clearance size will lead to the growth of incoming incidence angle near the tip of the rear rotor (R2). The increasing of double leakage flow range plays a significant role in the sensitivity of the efficiency to tip clearance size and its extent is enlarged gradually with the increase of tip clearance size. As the tip clearance size is increased to 1.5τ (τ represents the designed tip clearance size) from 0.5τ, the results of the fast Fourier transform for the static pressure near blade tip show that two other new fluctuating frequency components appear due to the happening of tip leakage flow self-unsteadiness in R1 and R2, respectively. Additionally, the fluctuating strength near the tip in R2 is significantly increased. However, both the overall fluctuation in R1 caused by the potential effect from downstream and the oscillation in the hub corner on the pressure side of R2 are decreased obviously. The relative inflow angle tends to increase when the incoming wakes and tip leakage flow from R1 encounter the blade leading edge of R2, which leads to the result that the trajectory of tip leakage flow is shifted more upstream.

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

1980 ◽  
Vol 102 (1) ◽  
pp. 50-60 ◽  
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.

Experimental Investigation of Stepped Tip Gap Effects on the Performance of a Transonic Axial-Flow Compressor Rotor

1997 ◽  
Author(s):  
Donald W. Thompson ◽  
Paul I. King ◽  
Douglas C. Rabe
Keyword(s):  
Mass Flow ◽  
Pressure Ratio ◽  
Axial Flow ◽  
Operating Conditions ◽  
Tip Clearance ◽  
Axial Flow Compressor ◽  
Transonic Compressor ◽  
Compressor Rotor ◽  
Compressor Performance ◽  
Flow Compressor

The effects of stepped tip gaps and clearance levels on the performance of a transonic axial-flow compressor rotor were experimentally determined. A two-stage compressor with no inlet guide vanes was tested in a modern transonic compressor research facility. The first-stage rotor was unswept and was tested for an optimum tip clearance with variations in stepped gaps machined into the casing near the aft tip region of the rotor. Nine casing geometries were investigated consisting of three step profiles at each of three clearance levels. For small and intermediate clearances, stepped tip gaps were found to improve pressure ratio, efficiency, and flow range for most operating conditions. At 100% design rotor speed, stepped tip gaps produced a doubling of mass flow range with as much as a 2.0% increase in mass flow and a 1.5% improvement in efficiency. This study provides guidelines for engineers to improve compressor performance for an existing design by applying an optimum casing profile.

Sign in / Sign up

Export Citation Format

Share Document