Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 120
Book Description
Full-coverage Film Cooling on Flat, Isothermal Surfaces: Data and Predictions
Full-coverage Film Cooling on Flat, Isothermal Surfaces
Author: Michael E. CrawfordPublisher:
ISBN:
Category : Boundary layer
Languages : en
Pages : 120
Book Description
An investigation of the heat transfer for full coverage film cooling of a flat plate with normal holes
Author: Grady Blair KellyScientific and Technical Aerospace Reports
Author: Surface Measurements and Predictions of Full-coverage Film Cooling
Author: Greg NatsuiPublisher:
ISBN:
Category :
Languages : en
Pages : 126
Book Description
Full-coverage film cooling is investigated both experimentally and numerically. First, surface measurements local of adiabatic film cooling eeffectiveness and heat transfer augmentation for four different arrays are described. Reported next is a comparison between two very common turbulence models, Realizable k-[epsilon] and SST k-[omega], and their ability to predict local film cooling effectiveness throughout a full-coverage array. The objective of the experimental study is the quantification of local heat transfer augmentation and adiabatic film cooling effectiveness for four surfaces cooled by large, both in hole count and in non-dimensional spacing, arrays of film cooling holes. The four arrays are of two different hole-to-hole spacings (P/D = X/D = 14.5; 19.8) and two different hole inclination angles ([alpha] = 30°; 45°), with cylindrical holes compounded relative to the flow ([beta] = 45°) and arranged in a staggered configuration. Arrays of up to 30 rows are tested so that the superposition effect of the coolant film can be studied. In addition, shortened arrays of up to 20 rows of coolant holes are also tested so that the decay of the coolant film following injection can be studied. Levels of laterally averaged effectiveness reach values as high as [eta with line above]= 0.5, and are not yet at the asymptotic limit even after 20-30 rows of injection for all cases studied. Levels of heat transfer augmentation asymptotically approach values of h=h0 [almost equal to] 1.35 rather quickly, only after 10 rows. It is conjectured that the heat transfer augmentation levels off very quickly due to the boundary layer reaching an equilibrium in which the perturbation from additional film rows has reached a balance with the damping effect resulting from viscosity. The levels of laterally averaged adiabatic film cooling effectiveness far exceeding [eta with line above]= 0.5 are much higher than expected. The heat transfer augmentation levels off quickly as opposed to the film effectiveness which continues to rise (although asymptotically) at large row numbers. This ensures that an increased row count represents coolant well spent. The numerical predictions are carried out in order to test the ability of the two most common turbulence models to properly predict full-coverage film cooling. The two models chosen, Realizable k-[epsilon] (RKE) and Shear Stress Transport k-[omega] (SSTKW), are both two-equation models coupled with Reynolds Averaged governing equations which make several gross physical assumptions and require several empirical values. Hence, the models are not expected to provide perfect results. However, very good average values are seen tobe obtained through these simple models. Using RKE in order to model full-coverage filmcooling will yield results with 30% less error than selecting SSTKW.
Film Cooling on a Convex Wall
Author: Kokichi FuruhamaPublisher:
ISBN:
Category : Turbines
Languages : en
Pages : 196
Book Description
Full-coverage Film Cooling Heat Transfer Studies - a Summary of the Data for Normal-hole Injection and 30 Degree Stant-hole Injection
Author: M. E. CrawfordPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Results are presented from a study of heat transfer to a full-coverage, film-cooled turbulent boundary layer over a flat surface. The surface used in the investigation consists of a discrete hole test section, containing eleven.
Film Cooling and Turbine Blade Heat Transfer
Author: Publisher:
ISBN:
Category : Aircraft gas-turbines
Languages : en
Pages : 262
Book Description
Advances in Heat Transfer
Author: Publisher: Academic Press
ISBN: 0080575706
Category : Science
Languages : en
Pages : 401
Book Description
Advances in Heat Transfer
Fluid Dynamics and Heat Transfer of Turbomachinery
Author: Budugur LakshminarayanaPublisher: John Wiley & Sons
ISBN: 9780471855460
Category : Technology & Engineering
Languages : en
Pages : 846
Book Description
Over the past three decades, information in the aerospace and mechanical engineering fields in general and turbomachinery in particular has grown at an exponential rate. Fluid Dynamics and Heat Transfer of Turbomachinery is the first book, in one complete volume, to bring together the modern approaches and advances in the field, providing the most up-to-date, unified treatment available on basic principles, physical aspects of the aerothermal field, analysis, performance, theory, and computation of turbomachinery flow and heat transfer. Presenting a unified approach to turbomachinery fluid dynamics and aerothermodynamics, the book concentrates on the fluid dynamic aspects of flows and thermodynamic considerations rather than on those related to materials, structure, or mechanical aspects. It covers the latest material and all types of turbomachinery used in modern-day aircraft, automotive, marine, spacecraft, power, and industrial applications; and there is an entire chapter devoted to modern approaches on computation of turbomachinery flow. An additional chapter on turbine cooling and heat transfer is unique for a turbomachinery book. The author has undertaken a systematic approach, through more than three hundred illustrations, in developing the knowledge base. He uses analysis and data correlation in his discussion of most recent developments in this area, drawn from over nine hundred references and from research projects carried out by various organizations in the United States and abroad. This book is extremely useful for anyone involved in the analysis, design, and testing of turbomachinery. For students, it can be used as a two-semester course of senior undergraduate or graduate study: the first semester dealing with the basic principles and analysis of turbomachinery, the second exploring three-dimensional viscid flows, computation, and heat transfer. Many sections are quite general and applicable to other areas in fluid dynamics and heat transfer. The book can also be used as a self-study guide to those who want to acquire this knowledge. The ordered, meticulous, and unified approach of Fluid Dynamics and Heat Transfer of Turbomachinery should make the specialization of turbomachinery in aerospace and mechanical engineering much more accessible to students and professionals alike, in universities, industry, and government. Turbomachinery theory, performance, and analysis made accessible with a new, unified approach For the first time in nearly three decades, here is a completely up-to-date and unified approach to turbomachinery fluid dynamics and aerothermodynamics. Combining the latest advances, methods, and approaches in the field, Fluid Dynamics and Heat Transfer of Turbomachinery features: The most comprehensive and complete coverage of the fluid dynamics and aerothermodynamics of turbomachinery to date A spotlight on the fluid dynamic aspects of flows and the thermodynamic considerations for turbomachinery (rather than the structural or material aspects) A detailed, step-by-step presentation of the analytical and computational models involved, which allows the reader to easily construct a flowchart from which to operate Critical reviews of all the existing analytical and numerical models, highlighting the advantages and drawbacks of each Comprehensive coverage of turbine cooling and heat transfer, a unique feature for a book on turbomachinery An appendix of basic computation techniques, numerous tables, and listings of common terminology, abbreviations, and nomenclature Broad in scope, yet concise, and drawing on the author's teaching experience and research projects for government and industry, Fluid Dynamics and Heat Transfer of Turbomachinery explains and simplifies an increasingly complex field. It is an invaluable resource for undergraduate and graduate students in aerospace and mechanical engineering specializing in turbomachinery, for research and design engineers, and for all professionals who are—or wish to be—at the cutting edge of this technology.