The Effect of Reaction on Axial Flow Compressor Performance

1994 ◽  
Author(s):  
C. D. Farmakalides ◽  
A. B. McKenzle ◽  
R. L. Elder
Keyword(s):  
Axial Flow ◽  
Flow Conditions ◽  
Performance Measurements ◽  
Operating Range ◽  
Axial Flow Compressor ◽  
High Reaction ◽  
Stable Operating ◽  
Compressor Performance ◽  
Institute Of Technology ◽  
Flow Compressor

This paper describes a study of the effects of design-point reaction on axial flow compressor performance. Particular attention is given to differences in stable operating range and overall efficiency. Design of an 80% reaction, zero pre-whirl, blading is presented together with a discussion on the applicability of currently available design correlations, mostly derived from 50% reaction blading tests, to such high reaction blading. Experimental data obtained from tests carried out on a low speed 3-stage axial flow research facility, at Cranfield Institute of Technology (now Cranfield University), using an existing 50% reaction blading and the new 80% reaction blading indicate that high reaction designs can result in improved operating range at no loss of efficiency. Tests carried out include performance measurements for each of the two bladings at various stator stagger settings and include inter-row radial traversing at flow conditions near optimum and stall.

Experimental Investigation on the Effect of Porosity of Bend Skewed Casing Treatment on a Single Stage Transonic Axial Flow Compressor

2014 ◽  
Author(s):  
Dilipkumar B. Alone ◽  
Subramani Satish Kumar ◽  
Shobhavathy Thimmaiah ◽  
Janaki Rami Reddy Mudipalli ◽  
A. M. Pradeep ◽  
...  
Keyword(s):  
Experimental Investigation ◽  
Axial Flow ◽  
Compressor Stage ◽  
Casing Treatment ◽  
Operating Range ◽  
Axial Flow Compressor ◽  
Transonic Compressor ◽  
Stable Operating ◽  
Flow Compressor ◽  
Casing Treatments

A bend skewed casing treatment was designed, to study the influence of one of its geometrical parameter porosity on the stable performance of single stage transonic axial flow compressor. The compressor was designed for the stage total-to-total pressure ratio of 1.35, corrected mass flow rate of 22 kg/s at corrected design speed of 12930 RPM. Bend skewed casing treatment has an axial inlet segment till 50% of the total length and rear segment that is skewed by 45° in the direction of the rotor tip section stagger. Both the sections were oriented at a skew angle of 45° to the radial plane such that the flow exiting the slot is in counter-clockwise direction to that of the rotor direction. The casing treatment slot width was equal to the maximum thickness of the rotor blades. Three casing treatment configurations were identified for the current experimental investigation. All the treatment geometries considered for the experimental research have lower porosities than reported in the open literatures. The effect of the porosity parameter on the performance of transonic compressor stage was evaluated at two axial coverages of 20% and 40% relative to the rotor tip axial chord. Performance maps were obtained for the solid casing and casing treatment with three different porosities. Comparative studies were carried out and experimental results showed a maximum of 65% improvement in the stable operating range of the compressor for one of the treatment configurations. It was also observed that the stable operating range of the compressor increases with an increase in the casing treatment porosity. All the casing treatment configurations showed that the compressor stall occurs at lower mass flows as compared to the solid casing. Compressor stage peak efficiency shows significant degradations with increase in the porosity as compared to solid casing. Detailed blade element performances were also obtained using calibrated multi-hole aerodynamic probe. Comparative variations of flow parameters like absolute flow angle, Mach number were studied at full flow and near stall conditions for the solid casing and casing treatment configurations. Hot wire measurements show very high fluctuation in the inlet axial velocity in the presence of solid casing as compared to casing treatments. Experimental investigation revealed that the porosity of the casing treatments has strong influence on the transonic compressor stage performance.

scholarly journals Axial-flow compressor analysis under distorted phenomena at transonic flow conditions

2018 ◽  
Vol 5 (1) ◽  
pp. 1526458
Author(s):  
G Srinivas ◽  
K Raghunandana ◽  
Shenoy B Satish ◽  
Duc Pham
Keyword(s):  
Transonic Flow ◽  
Axial Flow ◽  
Flow Conditions ◽  
Axial Flow Compressor ◽  
Flow 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.

scholarly journals CFD Analysis to Understand the Flow Behaviour of a Single Stage Transonic Axial Flow Compressor

2013 ◽  
Author(s):  
M. T. Shobhavathy ◽  
Premakara Hanoca
Keyword(s):  
Axial Flow ◽  
Flow Behaviour ◽  
Single Stage ◽  
Cfd Analysis ◽  
Flow Conditions ◽  
Blade Passage ◽  
Tip Leakage ◽  
Axial Flow Compressor ◽  
Design Speed ◽  
Flow Compressor

This paper comprises the Computational Fluid Dynamic (CFD) analysis to investigate the flow behaviour of a high speed single stage transonic axial flow compressor. Steady state analyses were carried out at design and part speed conditions to obtain the overall performance map using commercial CFD software ANSYS FLUENT. Radial distribution of flow parameters were obtained at 90% of design speed for the choked flow and near stall flow conditions. The predicted data were validated against available experimental results. The end wall flow fields were studied with the help of velocity vector plots and Mach number contours at peak efficiency and near stall flow conditions at 60% and 100% design speeds. This study exhibited the nature of a transonic compressor, having strong interaction between the rotor passage shock and the tip leakage vortex at design speed, which generates a region of high blockage in the rotor blade passage. The influence of this interaction extends around15% of the blade outer span at design speed and in the absence of blade passage shock at 60% design speed, the influence of tip leakage flow observed was around 8%.

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.

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.

Sign in / Sign up

Export Citation Format

Share Document