Effect of Axial Velocity Density Ratio on the Performance of a Controlled Diffusion Airfoil Compressor Cascade
-
R. Senthil Kumaran
,
Sachin Kamble
Abstract
Axial Velocity Density Ratio (AVDR) is an important parameter to check the two-dimensionality of cascade flows. It can have significant influence on the cascade performance and the secondary flow structure. In the present study, the effect of AVDR has been investigated on a highly loaded Controlled Diffusion airfoil compressor cascade. Detailed 3D Computational Fluid Dynamics (CFD) studies were carried out with the cascade at five different AVDRs. Key aerodynamic performance parameters and flow structure through the cascade were analyzed in detail. CFD results of one AVDR were validated with the experimental cascade test data and were seen to be in good agreement. Loss characteristics of the cascade varied significantly with change in AVDR. Increase in AVDR postponed the point of separation on the suction surface, produced thinner boundary layers and caused substantial drop in the pressure loss coefficient. Strong end wall vortices were noticed at AVDR of 1.177. At higher AVDRs, the flow was well guided even close to the end wall and the secondary flows diminished. The loading initially improved with increase in AVDR. Beyond a certain limit, further increase in AVDR offered no improvements to the loading but rather resulted in drop in diffusion and deviation.
Nomenclature
- Symbol
Description
- C
Chord
- Cx
Axial chord
- s
Pitch
- o
Throat
- t
Maximum blade thickness
- M
Mach number
- P
Pressure
- V
Velocity
- k
Turbulent kinetic energy
- x
x-direction
- y
y-direction
- y+
Dimensionless wall distance
- β
Flow angle
- βs
Stagger angle
- ψ
Metal angle
- ρ
Density
- Ω
Pressure loss coefficient
- ω
Specific dissipation rate
- γ
Ratio of specific heats
- Abbreviations
Full Form
- AR
Area Ratio
- AVDR
Axial Velocity Density Ratio
- CAD
Computer-Aided Design
- CD
Controlled Diffusion
- CFD
Computational Fluid Dynamics
- CSIR
Council of Scientific & Industrial Research, India
- DCA
Double Circular Arc
- LE
Leading Edge
- NACA
National Advisory Committee for Aeronautics
- NAL
National Aerospace Laboratories
- RANS
Reynolds Averaged Navier–Stokes Equation
- SST
Shear Stress Transport
- TCT
Transonic Cascade Tunnel
- TE
Trailing Edge
- Subscripts
Description
- isen
Isentropic
- 0
Stagnation
- 1
Inlet
- 2
Outlet/exit
- y
Local point in the wake
Acknowledgments
The authors wish to express gratitude to all those who helped in carrying out this work successfully. The authors thank the management of CSIR-National Aerospace Laboratories (NAL), Bangalore, for permitting to take up this research work and for allowing it to be published. The authors sincerely thank the president, M S Ramiah University of Applied Sciences, Bangalore, for the support extended during the course of this research.
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©2015 by De Gruyter
Articles in the same Issue
- Frontmatter
- Effect of Axial Velocity Density Ratio on the Performance of a Controlled Diffusion Airfoil Compressor Cascade
- Uncertainty Analysis in Fatigue Life Prediction of Gas Turbine Blades Using Bayesian Inference
- A New Turbo-shaft Engine Control Law during Variable Rotor Speed Transient Process
- Numerical Study of a Fuel Centrifugal Pump with Variable Impeller Width for Aero-engines
- Analysis of Ablative Performance of C/C Composite Throat Containing Defects Based on X-ray 3D Reconstruction in a Solid Rocket Motor
- Effects of Circumferential Casing Grooves on the Performance of a Transonic Axial Compressor
Articles in the same Issue
- Frontmatter
- Effect of Axial Velocity Density Ratio on the Performance of a Controlled Diffusion Airfoil Compressor Cascade
- Uncertainty Analysis in Fatigue Life Prediction of Gas Turbine Blades Using Bayesian Inference
- A New Turbo-shaft Engine Control Law during Variable Rotor Speed Transient Process
- Numerical Study of a Fuel Centrifugal Pump with Variable Impeller Width for Aero-engines
- Analysis of Ablative Performance of C/C Composite Throat Containing Defects Based on X-ray 3D Reconstruction in a Solid Rocket Motor
- Effects of Circumferential Casing Grooves on the Performance of a Transonic Axial Compressor
