Impingement Jet Cooling in Gas Turbines

Buch | Hardcover

250 Seiten

2014
WIT Press (Verlag)
978-1-84564-906-7 (ISBN)

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Due to the requirement for enhanced cooling technologies on modern gas turbine engines, advanced research and development has had to take place in field of thermal engineering. Among the gas turbine cooling technologies, impingement jet cooling is one of the most effective in terms of cooling effectiveness, manufacturability and cost. The chapters contained in this book describe research on state-of-the-art and advanced cooling technologies that have been developed, or that are being researched, with a variety of approaches from theoretical, experimental, and CFD studies. The authors of the chapters have been selected from some of the most active researchers and scientists on the subject. This is the first to book published on the topics of gas turbines and heat transfer to focus on impingement cooling alone.

Contents CHAPTER 1 Impingement Cooling in Gas Turbines: Design, Applications, and Limitations Introduction; Applications; Single-jet impingement cooling; Impingement from in-line jet rows; Leading edge cooling; Trailing edge cooling; Surface jet array impingement; Inner and outer flow path cooling; Rotating disk impingement; Impingement in rotating cooling passages; Confined channel impingement; Impingement onto randomly rough and textured surfaces; Blade tip internal cooling; Combustor cooling; Closed-circuit impingement cooling; Impingement in film cooling; Limitations; Summary; Nomenclature; References CHAPTER 2 Impingement Jet Cooling with Different Stand-Off Distances for Single- and Double-Exit Flows Introduction; Cooling Jet Array; Turbulence Models; SST model; V2F model;Presentation and Discussion of Results; Single-exit flow cases; Prediction using different turbulence models; y+ distribution; Large eddy simulation (LES); V2F computations; Reynolds number effect; Double-exit flow cases; Reynolds number dependence on heat transfer rate; Non-circular holes; Staggered array; Summary; Acknowledgements; References CHAPTER 3 Recent Developments in Impingement Array Cooling, Including Consideration of the Separate Effects of Mach Number, Reynolds Number, Temperature Ratio, Hole Spacing, and Jet-to-Target-Plate Distance Introduction; Experimental Apparatus and Procedures; Impingement flow facility and impingement array plates; Discharge coefficient measurement and determination; Local recovery factor measurement; Local Nusselt number measurement; Experimental Results and Discussion; Crossflow mass velocity-to-jet mass velocity ratio and discharge coefficients; Separate effects of Reynolds number and Mach number on impingement array heat transfer; Determination of spatially averaged adiabatic surface temperature, Toj*; Nusselt number variations with Mach number and Reynolds number; Comparisons of spatially averaged Nusselt numbers with existing correlations, and a new correlation to account for Mach number effects; Recovery factor data; Nusselt number data corrected using local recovery factors; Effects of temperature ratio on impingement array heat transfer; Local surface Nusselt number variations with temperature ratio; Spatially averaged Nusselt number variations with temperature ratio; Spatially averaged Nusselt numbers and the temperature ratio correlation equation; Effects of hole spacing on impingement array heat transfer; Line-averaged Nusselt numbers; Spatially averaged Nusselt numbers; Correlations to account for compressibility on spatially averaged Nusselt numbers with different hole spacings; Effects of jet-to-target-plate distance on impingement array heat transfer; Spatially resolved local Nusselt numbers; Spatially averaged Nusselt numbers; Summary and Conclusions; Acknowledgments; Nomenclature; Greek symbols; References CHAPTER 4 Impingement Cooling for Combustor Liner Backside Cooling Introduction; Background; Jet Impingement Cooling; Effect of initial crossflow; Impingement cooling for combustor liners; Conclusions; References CHAPTER 5 Impingement/Effusion Cooling Methods in Gas Turbine Introduction; Heat Transfer of Impingement/Effusion Cooling; Fundamentals of impingement/effusion cooling; Basic concepts of impingement/effusion cooling; Heat transfer characteristics of array jet impingement; Comparison of impingement jet and impingement/effusion cooling; Major Variables for Impingement/Effusion Cooling; Effect of hole pattern and arrangement; Effect of plate spacing; Effect of Reynolds number; Effect of surface curvature; Effect of crossflow; Effect of surface modification; Rib turbulators; Pin-fins; References CHAPTER 6 Flow Control of Impingement Jets and Wall Jets Introduction to Flow Control of Impinging Jet; Passive Control of Jet Impingement; Passive control at nozzle; Flow at nozzle exit; 2.1.2Nozzle geometry;Passive control at target surface; Protrusion; Dimple; Surface curvature; Impingement on rotating disk; Inclined jet impingement; Active Control of Jet Impingement; Active flow control at nozzle; Pulsation of jet; Shear layer excitation; Active flow control at target surface; Summary; References CHAPTER 7 Numerical Simulation of Heat Transfer from Impinging Swirling Jets Introduction; Governing Equations; Numerical Approach; Turbulence and turbulence modeling;The RNG k - model; The SST k - model; The RSM model; The V2f model; Near wall treatment; Results and Discussion; Basic test case - reveal of physical influence of swirl; Turbulent swirling impinging jet; Calculations vs. experiments by Bilen et al. [33]; Calculations vs. experiments by Huang and El-Genk [35]; Conclusions; Acknowledgement; Nomenclature; Greek symbols; Subscripts; References CHAPTER 8 Experimental and Numerical Study on Heat Transfer Enhancement of Impingement Jet Cooling by Adding Ribs on Target Surface Introduction; Experimental Study; Heat transfer test with two-dimensional impinging jet nozzle; Heat transfer test with circular impinging jet nozzle; Naphthalene sublimation method; Results and discussion; Two-dimensional impinging jet nozzle; Circular impingement jet nozzle; Numerical Study; Rib-enhanced two-dimensional jet impingement heat transfer; Numerical method for RANS; Numerical method for LES; Results and discussion; Round jet impingement heat transfer enhanced by circular rib; Numerical setup; Results and discussion; Summary; References

Reihe/Serie	Developments in Heat Transfer ; 25
Zusatzinfo	Illustrations
Verlagsort	Southampton
Sprache	englisch
Maße	156 x 234 mm
Themenwelt	Naturwissenschaften ► Physik / Astronomie ► Thermodynamik
	Technik ► Elektrotechnik / Energietechnik
	Technik ► Maschinenbau
ISBN-10	1-84564-906-0 / 1845649060
ISBN-13	978-1-84564-906-7 / 9781845649067
Zustand	Neuware