scholarly journals Temperature Rise in the Multistage Axial Flow Compressor During Rotating Stall and Surge

1988 ◽  
Author(s):  
Katerina Nácovská
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Axial Flow ◽  
Rotating Stall ◽  
Rotor Speed ◽  
Absolute Level ◽  
Axial Flow Compressor ◽  
Temperature Levels ◽  
Flow Compressor

An experimental investigation of rotating stall and surge was carried out on a four stage axial flow compressor. Results of flow and blade temperature measurements in the compressor are presented. Internal temperature levels during rotating stall and surge are considerably higher than those obtained during unstalled compressor operation. In the pure rotating stall regime, the temperature is almost identical in all compressor stages and depends only on rotor speed and mass flow rate. During surge, the highest temperature is found at the tip diameter prior to the first stage rotor. The absolute level depends on rotor speed, mass flow rate (i.e. throttle position) and on the number of compressor stages. A model of the temperature changes in the multistage compressor during the surge cycle has been derived from the experiments.

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%.

Parametric Study of Tip Injection in an Axial Flow Compressor Stage

2007 ◽  
Author(s):  
Gabriele Cassina ◽  
Behnam H. Beheshti ◽  
Albert Kammerer ◽  
Reza S. Abhari
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Rotor Blade ◽  
Axial Flow ◽  
Axial Flow Compressor ◽  
Stable Operating ◽  
Operating Margin ◽  
Tip Injection ◽  
Flow Compressor

Tip injection upstream of the rotor blade is a well-known technique for suppressing instabilities in axial compressors and recovering from a fully developed stall. In tip critical rotors, tip injection can effectively increase the blade loading and the stable operating margin of compressors by unloading the rotor tip. Compared to fully annular injection, discrete tip injection is better able to increase the compressor stability. This paper presents a numerical study of the effects of discrete upstream air injection on the stability of an axial flow compressor. Reynolds-averaged Navier-Stokes equations have been solved using ANSYS CFX with a k-epsilon turbulence model for three compressor blade passages. To validate the simulations, mass flow rate, pressure ratio, and efficiency at the compressor design point have been computed and compared to experimental data and results are in good agreement. For simulation of tip injection, 10 axisymmetric, but circumferentially discrete injectors, positioned at 50% of the blade axial chord upstream of the rotor blade leading edge, have been modelled. The ports are mounted on the casing and provide high-pressure jet of air at a 15° angle in the radial direction. To study the effects of injection, the compressor map at design speed has been compared for the models with and without injection. Results indicate that tip injection improves the compressor stability by unloading the rotor tip. Simulations show that by increasing the injection mass flow, the compressor stable operating margin can be improved. Simulations also predict optimum values for the injection port width-to-length ratio and the injection angle when the injection mass flow rate and area are kept constant. Further studies have been done to investigate the effect of the axial position of the injector.

Active Flow Control for Increasing the Surge Margin of an Axial Flow Compressor

2006 ◽  
Author(s):  
M. Kefalakis ◽  
K. D. Papailiou
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Active Flow Control ◽  
Axial Flow ◽  
Axial Flow Compressor ◽  
Surge Margin ◽  
Pulsating Jet ◽  
Pulsating Jets ◽  
Flow Compressor

Steady and pulsating jets were used targeting to increase the surge margin of an axial flow compressor. In this experimental study, a rotating valve was built for generating pulsating jets and a number of pulsating jet actuators were installed on the compressor casing. Approximately 10% surge margin increase was obtained for a jet mass flow rate of less than 1% of the compressor mass flow rate. The active control mechanism is analyzed and the influence of each parameter is studied in an effort to quantify their relative influence and increase our understanding of the phenomenon.

Experimental investigations on instability evolution in a transonic compressor at different rotor speeds

2015 ◽  
Vol 229 (18) ◽  
pp. 3378-3391 ◽  
Author(s):  
Qiushi Li ◽  
Tianyu Pan ◽  
Tailu Sun ◽  
Zhiping Li ◽  
Yifang Gong
Keyword(s):  
Low Frequency ◽  
Axial Flow ◽  
Rotating Stall ◽  
Operating Conditions ◽  
Experimental Investigations ◽  
Rotor Speed ◽  
Axial Flow Compressor ◽  
Transonic Compressor ◽  
New Type ◽  
Flow Compressor

Experimental investigations are conducted to study the instability evolution in a transonic axial flow compressor at four specific rotor speeds covering both subsonic and transonic operating conditions. Two routes of evolution to final instability are observed in the test compressor: at low rotor speeds, a disturbance in the rotor tip region occurs and then leads to rotating stall, while at high rotor speeds, a low-frequency disturbance in the hub region leads the compressor into instability. Different from stall and surge, this new type of compressor instability at high rotor speed is initiated through the development of a low-frequency axisymmetric disturbance at the hub, and we name it “partial surge”. The frequency of this low-frequency disturbance is approximately the Helmholtz frequency of the system and remains constant during instability inception. Finally, a possible mechanism for the occurrence of different instability evolutions and the formation of partial surge are also discussed.

Stator-Rotor Interactions in a Transonic Compressor— Part 1: Effect of Blade-Row Spacing on Performance

2003 ◽  
Vol 125 (2) ◽  
pp. 328-335 ◽  
Author(s):  
Steven E. Gorrell ◽  
Theodore H. Okiishi ◽  
William W. Copenhaver
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Pressure Ratio ◽  
Axial Flow ◽  
Transonic Compressor ◽  
Blade Row ◽  
Spacing Variation ◽  
Stator Blade ◽  
Flow Compressor

Usually less axial spacing between the blade rows of an axial flow compressor is associated with improved efficiency. However, mass flow rate, pressure ratio, and efficiency all decreased as the axial spacing between the stator and rotor was reduced in a transonic compressor rig. Reductions as great as 3.3% in pressure ratio, and 1.3 points of efficiency were observed as axial spacing between the blade rows was decreased from far apart to close together. The number of blades in the stator blade-row also affected stage performance. Higher stator blade-row solidity led to larger changes in pressure ratio efficiency, and mass flow rate with axial spacing variation. Analysis of the experimental data suggests that the drop in performance is a result of increased loss production due to blade-row interactions. Losses in addition to mixing loss are present when the blade-rows are spaced closer together. The extra losses are associated with the upstream stator wakes and are most significant in the midspan region of the flow.

scholarly journals Characterizing the Effects of Air Injection on Compressor Performance for Use in Active Control of Rotating Stall

1997 ◽  
Author(s):  
Robert L. Behnken ◽  
Mina Leung ◽  
Richard M. Murray
Keyword(s):  
Hysteresis Loop ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Axial Flow ◽  
Open Loop ◽  
Rotating Stall ◽  
Air Injection ◽  
Loop Control ◽  
Flow Compression

Previous work has developed an air injection controller for rotating stall based on the idea of a shifting compressor characteristic and the Moore-Greitzer three state compressor model. In order to demonstrate this form of control experimentally, a series of open loop tests were performed to measure the performance characteristics of a low speed axial flow compression system when air is injected upstream of the rotor face. The position of the air injection port relative to the hub and the rotor face and the angle relative to the mean axial flow were varied. The tests show that the injection of air has drastic effects on the stalling mass flow rate and on the size of the hysteresis loop associated with rotating stall. The stalling mass flow rate was decreased by 10% and the hysteresis loop was completely eliminated under some conditions. The results of the open loop parametric study were then used to implement a closed loop control strategy based on a shifting characteristic.

Stator-Rotor Interactions in a Transonic Compressor: Part 1 — Effect of Blade-Row Spacing on Performance

2002 ◽  
Author(s):  
Steven E. Gorrell ◽  
Theodore H. Okiishi ◽  
William W. Copenhaver
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Pressure Ratio ◽  
Axial Flow ◽  
Transonic Compressor ◽  
Blade Row ◽  
Spacing Variation ◽  
Stator Blade ◽  
Flow Compressor

Usually less axial spacing between the blade rows of an axial flow compressor is associated with improved efficiency. However, mass flow rate, pressure ratio, and efficiency all decreased as the axial spacing between the stator and rotor was reduced in a transonic compressor rig. Reductions as great as 3.3% in pressure ratio and 1.3 points of efficiency were observed as axial spacing between the blade-rows was decreased from far apart to close together. The number of blades in the stator blade-row also affected stage performance. Higher stator blade-row solidity led to larger changes in pressure ratio, efficiency, and mass flow rate with axial spacing variation. Analysis of the experimental data suggests that the drop in performance is a result of increased loss production due to blade-row interactions. Losses in addition to mixing loss are present when the blade-rows are spaced closer together. The extra losses are associated with the upstream stator wakes and are most significant in the mid-span region of the flow.

Sign in / Sign up

Export Citation Format

Share Document