文摘
英文文摘
Dedication
Acknowledgements
Nomenclature
CHAPTER 1 INTRODUCTION
1.1 General
1.2 Research objective
1.3 Major steps in the present research
CHAPTER 2 BACKGROUND/LITERATURE REVIEW
2.1 Introduction
2.2.1 Secondary flow models
2.2.2 Computational fluid dynamics(CFD)
2.2.3 Particle image velocimetry
2.2.4 Tip leakage flow studies
CHAPTER 3 STUDY OF TIP VORTEX AND WAKE IN OPEN AXIAL FLOW FAN USING PIV TECHNIQUE
3.1 Introduction
3.2 Particle Image Velocimetry Technique
3.2.1 Principle of PIV technique
3.2.2 Particle Image Velocimetry system components
3.3 Description of the present test facility
3.3.1 Midea PIV system
3.4 Open axial flow fan geometric data
3.5 Measurement station locations
3.6 Experimental stet up and Procedures
3.7 PIV results and discussion
3.7.1 Prediction of blade tip vortex by PIV
3.7.2 Determination of tip vortex area, range and direction
3.7.3 Tip vortex flow structures
3.7.4 Prediction of wake flow using PIV
3.8 Effect of rotational speed on tip vortex and wake
CHAPTER 4 NUMERICAL SIMULATION TECHNIQUES AND ITS VALIDATION
4.1 Introduction
4.2 Governing equations
4.2.1 Navier-Stokes equations.
4.2.2 Turbulence model equations
4.3 Discritization form
4.3.1 Second order Upwind Scheme
4.3.2 Pressure Correction Equation
4.4 Summary of computational method steps
4.5 Computational models
4.6 CFD code validation
4.6.1 Application of CFD code to model-1
4.6.2 Application of the CFD code to model-2
4.6.3 Application of the CFD code to model-3
CHAPTER 5 NUMERICAL SIMULATION AND MODIFICATION OF 3D FLOW PHENOMENA IN AXIAL FLOW FAN
5.1 Introduction
5.2 Design method
5.2.1 Model of fan geometry
5.3 Boundary conditions
5.4 Grid generation
5.5 Results and discussion
5.5.1 Overall performance
5.5.2 Determination of high-vortex regions.
5.5.3 Flow at rotor exit
5.5.4 Stator flow pattern
CHAPTER 6 SIMULATION OF TIP LEAKAGE FLOWS AND THEIR EFFECTS IN ISOLATED AXIAL FLOW FAN ROTOR
6.1 Introduction
6.2 Model of fan geometry
6.3 Numerical simulation
6.3.1 Grid generation
6.3.2 Boundary conditions
6.4 Results and discussion
6.4.1 Effects of Tip clearance size on fan performance
6.4.2 Flow feature inside tip clearance
6.4.3 Determination of tip leakage vortex core locations at different conditions
6.4.4 Variation of pressure in and near the tip clearance region
6.4.5 Tip leakage effects on suction side
6.4.6 Tip clearance effects on flow at rotor exit
6.4.7 Tip clearance effects on wake flow
CHAPTER 7 CONCLUSIONS AND RECOMENDATIONS
7.l Conclusions
7.2 Recommendations
REFRENCES
Appendix-A QUASI-THREE DIMENSIONAL DESIGN METHOD
A.1 Basic concept of this method
A.2 Meridional through-flow calculation
A.3 Blade element selection on the average stream surface
Appendix-B RECENT PAPERS
