Download or read book Computational Film Cooling Methods for Gas Turbine Airfoils written by and published by . This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A previously documented CFD methodology is further generalized and applied to realistic turbine airfoil film cooling test cases. First, a series of fundamental test cases are examined in order to document the ability of the robust and practical CFD methodology to deal with the effects of the individually isolated key physics mechanisms on film cooling. These include: (1) favorable and adverse pressure gradients; (2) convex curvature; (3) horseshoe vortex; (4) profile losses with and without coolant jets; (5) laminar-to-turbulent boundary layer transition; and (6) discontinuities. Second, in addition to the fundamental flow test cases, two turbine airfoil cascade, one low subsonic and another transonic, configurations were modeled. The subsonic cascade case was designed to study the aerodynamics losses with and without film cooling jets, as well as, the adiabatic effectiveness for a range of parameters. The transonic turbine cascade represents a truly modern design at realistic engine conditions. A total of 18 test configurations, corresponding to compound-round, axial-shaped, and compound-shaped film holes, are simulated in order to document in detail the current state of the readily available robust and practical CFD technology for use by the gas turbine design community.

Download or read book A computational study for the utilization of jet pulsations in gas turbine film cooling and flow control written by Olga Valeryevna Kartuzova and published by . This book was released on 2012 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Gas Turbine Heat Transfer and Cooling Technology Second Edition written by Je-Chin Han and published by CRC Press. This book was released on 2012-11-27 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive reference for engineers and researchers, Gas Turbine Heat Transfer and Cooling Technology, Second Edition has been completely revised and updated to reflect advances in the field made during the past ten years. The second edition retains the format that made the first edition so popular and adds new information mainly based on selected published papers in the open literature. See What’s New in the Second Edition: State-of-the-art cooling technologies such as advanced turbine blade film cooling and internal cooling Modern experimental methods for gas turbine heat transfer and cooling research Advanced computational models for gas turbine heat transfer and cooling performance predictions Suggestions for future research in this critical technology The book discusses the need for turbine cooling, gas turbine heat-transfer problems, and cooling methodology and covers turbine rotor and stator heat-transfer issues, including endwall and blade tip regions under engine conditions, as well as under simulated engine conditions. It then examines turbine rotor and stator blade film cooling and discusses the unsteady high free-stream turbulence effect on simulated cascade airfoils. From here, the book explores impingement cooling, rib-turbulent cooling, pin-fin cooling, and compound and new cooling techniques. It also highlights the effect of rotation on rotor coolant passage heat transfer. Coverage of experimental methods includes heat-transfer and mass-transfer techniques, liquid crystal thermography, optical techniques, as well as flow and thermal measurement techniques. The book concludes with discussions of governing equations and turbulence models and their applications for predicting turbine blade heat transfer and film cooling, and turbine blade internal cooling.

Download or read book Prediction of Film Cooling on Gas Turbine Airfoils written by and published by . This book was released on 1994 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental and Computational Studies of Film Cooling with Compound Angle Injection written by and published by . This book was released on 1995 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: The thermal efficiency of gas turbine systems depends largely on the turbine inlet temperature. Recent decades have seen a steady rise in the inlet temperature and a resulting reduction in fuel consumption. At the same time, it has been necessary to employ intensive cooling of the hot components. Among various cooling methods, film cooling has become a standard method for cooling of the turbine airfoils and combustion chamber walls. The University of Minnesota program is a combined experimental and computational study of various film-cooling configurations. Whereas a large number of parameters influence film cooling processes, this research focuses on compound angle injection through a single row and through two rows of holes. Later work will investigate the values of contoured hole designs. An appreciation of the advantages of compound angle injection has risen recently with the demand for more effective cooling and with improved understanding of the flow; this project should continue to further this understanding. Approaches being applied include: (1) a new measurement system that extends the mass/heat transfer analogy to obtain both local film cooling and local mass (heat) transfer results in a single system, (2) direct measurement of three-dimensional turbulent transport in a highly-disturbed flow, (3) the use of compound angle and shaped holes to optimize film cooling performance, and (4) an exploration of anisotropy corrections to turbulence modeling of film cooling jets.

Download or read book Effects of Film Cooling on Turbine Blade Tip Flow Structures and Thermal Loading written by Louis Edward Christensen and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas turbine engines are an essential technology in aviation and power generation. One of the challenges associated with increasing the efficiency of gas turbines is the thermal loading experienced by the engine components downstream of the combustors especially the high-pressure turbine blades. High temperatures and rotational velocities can cause blade failures in numerous ways such as creep or stress rupture. Technologies like film cooling are implemented in these components to lower the thermal loading and reduce the risk of failure. However, these introduce complexities into the flow which in turn increases the difficulty of predicting the performance of film cooled turbines. Accurately predicting the capabilities of these components is essential to prevent failure in gas turbine engines. Engineers use a combination of experiments and computational simulations to understand how these technologies perform and predict the operating conditions and lifespan of these components. A combined experimental and numerical program is performed on a single stage high-pressure turbine to increase understanding of film cooling in gas turbines and improve computational methods used to predict their performance. The turbine studied is a contemporary production model from Honeywell Aerospace with both cooled and uncooled turbine blades. The experimental work is performed at The Ohio State University Gas Turbine Laboratory Turbine Test Facility, a short duration facility operating at engine corrected conditions. The experiments capture heat flux, temperature, and pressure data across the entire blade, but this work will focus on the turbine blade tip data. Tip temperature data are captured using a high-speed infrared camera providing a unique data set unseen in the current literature. In addition to the experiments, transient conjugate heat transfer simulations of a single turbine passage are performed to recreate the experiments and give insight into the flow field in the tip region of the turbine blades. The experiments and simulations are conducted to provide a better understanding of the interactions of the film cooling and tip flows along with their relationship to the thermal loading on the turbine blade tip. Film cooling in the tip region adds complexity to the flow and a non-intuitive relationship exists between film cooling and thermal loading. Addition of cooling is not guaranteed to reduce the thermal loading on the blade tips. Cooling jets can displace hot gases protecting the blade, but they are also capable of shifting flow structures and trapping hot gases near the blade surface especially so in corners of the blade tips. These direct and indirect methods of altering the thermal loading open a new path to optimization where engineers consider how the coolant alters the flow in addition to forming a protective layer of cool gas. This can be done to more effectively use coolant not only in the blade tips but elsewhere on the turbine blades leading to higher engine efficiencies and more sustainable gas turbine engines.

Download or read book Fundamental Heat Transfer Research for Gas Turbine Engines written by and published by . This book was released on 1980 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effects of Leading Edge and Downstream Film Cooling on Turbine Vane Heat Transfer written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-23 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: The progress under contract NAS3-24619 toward the goal of establishing a relevant data base for use in improving the predictive design capabilities for external heat transfer to turbine vanes, including the effect of downstream film cooling with and without leading edge showerhead film cooling. Experimental measurements were made in a two-dimensional cascade previously used to obtain vane surface heat transfer distributions on nonfilm cooled airfoils under contract NAS3-22761 and leading edge showerhead film cooled airfoils under contract NAS3-23695. The principal independent parameters (Mach number, Reynolds number, turbulence, wall-to-gas temperature ratio, coolant-to-gas temperature ratio, and coolant-to-gas pressure ratio) were maintained over ranges consistent with actual engine conditions and the test matrix was structured to provide an assessment of the independent influence of parameters of interest, namely, exit Mach number, exit Reynolds number, coolant-to-gas temperature ratio, and coolant-to-gas pressure ratio. Data provide a data base for downstream film cooled turbine vanes and extends the data bases generated in the two previous studies. The vane external heat transfer obtained indicate that considerable cooling benefits can be achieved by utilizing downstream film cooling. The data obtained and presented illustrate the interaction of the variables and should provide the airfoil designer and computational analyst the information required to improve heat transfer design capabilities for film cooled turbine airfoils. Hylton, L. D. and Nirmalan, V. and Sultanian, B. K. and Kaufman, R. M. Unspecified Center EQUIPMENT SPECIFICATIONS; FILM COOLING; HEAT TRANSFER; LEADING EDGES; STRUCTURAL DESIGN; VANES; AIRCRAFT ENGINES; CASCADE FLOW; DATA PROCESSING; GAS TURBINES; HIGH TEMPERATURE; PARAMETERIZATION; TWO DIMENSIONAL FLOW...

Download or read book Computational Methods and Experimental Measurements XV written by G. M. Carlomagno and published by WIT Press. This book was released on 2011 with total page 737 pages. Available in PDF, EPUB and Kindle. Book excerpt: Containing edited versions of most of the papers presented at the Fifteenth International Conference on Computational Methods and Experimental Measurements, this book reviews the latest work on these two approaches, and the interaction between them.

Download or read book Analysis of Combined Convective and Film Cooling on an Existing Turbine Blade written by and published by . This book was released on 2003 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: To support gas turbine operators NLR is developing capabilities for life assessment of hot engine components. As a typical example the first rotor blades of the high pressure (HP) turbine of the F-lOO-PW-220 military turbofan will be discussed. For these blades tools have been developed to derive the blade temperature history from flight data obtained from F-16 missions. The resulting relative life consumption estimate should support the Royal Netherlands Air Force in their engine maintenance activities. The present paper describes the prediction method for the blade temperature based on reverse engineering. Input data are the flight data of the engine performance parameters and the geometry of the HP turbine blades and vanes including film cooling orifices. The engine performance parameters are converted in HP turbine entry and exit conditions by the NLR Gas Turbine Simulation Program (GSP) engine model. Next a Computational Fluid dynamics (CFD) tool is used to calculate the resulting flow field and heat transfer coefficients without film cooling. An engineering method is used to predict the internal cooling and the resulting film injection temperature. The film cooling efficiency is estimated and a finite element method (FEM) for heat conduction completes the analysis tool. The method is illustrated by results obtained for the engine design point.

Download or read book Numerical Simulations of Leading Edge Film Cooling Flows for Gas Tubine Airfoils written by Cheryl A. Martin and published by . This book was released on 1997 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Computational Methods in Heat Transfer IX written by Bengt Sundén and published by WIT Press. This book was released on 2006 with total page 513 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat Transfer topics are commonly of a very complex nature. Often different mechanisms like heat conduction, convection, thermal radiation, and non-linear phenomena, such as temperature-dependent thermophysical properties, and phase changes occur simultaneously. New developments in numerical solution methods of partial differential equations and access to high-speed, efficient and cheap computers have led to dramatic advances during recent years. This book publishes papers from the Ninth International Conference on Advanced Computational Methods and Experimental Measurements in Heat and Mass Transfer, exploring new approaches to the numerical solutions of heat and mass transfer problems and their experimental measurement. Papers encompass a number of topics such as: Diffusion and Convection; Conduction; Natural and Forced Convection; Heat and Mass Transfer Interaction; Casting, Welding, Forging and other Processes; Heat Exchanges; Atmospheric Studies; Advances in Computational Methods; Modelling and Experiments; Micro and Nano Scale Heat and Mass Transfer; Energy Systems; Energy Balance Studies; Thermal Material Characterization; Applications in Biology; Applications in Ecological Buildings; Case Studies.

Download or read book Heat Transfer in Gas Turbines written by Bengt Sundén and published by Witpress. This book was released on 2001 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt: This title presents and reflects current active research on various heat transfer topics and related phenomena in gas turbine systems. It begins with a general introduction to gas turbine heat transfer, before moving on to specific areas.

Download or read book Unsteady Characterization of Film Cooling Flows on a Rotating High pressure Turbine written by Spencer J. Sperling and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas turbine performance is highly dependent on turbine inlet temperature, which often exceeds the working limitations of the materials involved. Film cooling is a widely used technology enabling highly efficient gas turbine cycles, where relatively cold air is injected as a film on the airfoil surfaces protecting the airfoils from the hot combustion gasses. Film cooled turbines exist in highly unsteady environments due to interactions between stationary and rotating components, and film cooling further complicates the flow. There is limited understanding of the unsteady nature of film cooling flows, resulting in limited ability to predict heat transfer and metal temperature on the components of a gas turbine. The goal of this work is to increase understanding of turbine cooling technology by examining time-accurate and time-averaged behaviors of the cooling flows. This dissertation incorporates experimental and computational analysis of pressure and heat transfer on an industry scale high-pressure turbine stage. Experimental measurements of pressure and heat transfer were performed on a turbine stage installed in the Turbine Test Facility at the Gas Turbine Laboratory. This facility is uniquely equipped to examine unsteady pressure and heat transfer on turbine stages operating at design corrected conditions. Heat transfer measurements are compared for multiple different cooling configurations on the rotating airfoils. Data are analyzed on time-averaged and time-resolved bases, and the results highlight cooling benefit differences among the various cooling hole shapes and coolant flow rates. Computational models of the turbine stage are also employed with steady and unsteady RANS modeling techniques. Experimental data are used for boundary conditions in the computational models as well as to evaluate the accuracy of the models. Comparisons of experimental and steady computations of film cooled turbines often result in poor agreement due to the complexity of film cooling flows.

Download or read book Advanced Computational Methods and Experiments in Heat Transfer X written by Bengt Sundén and published by WIT Press. This book was released on 2008-06-19 with total page 241 pages. Available in PDF, EPUB and Kindle. Book excerpt: In engineering design and development, reliable and accurate computational methods are requested to replace or complement expensive and time consuming experimental trial and error work. Tremendous advancements have been achieved during recent years due to improved numerical solutions of non-linear partial differential equations and computer developments to achieve efficient and rapid calculations. Nevertheless, to further progress in computational methods will require developments in theoretical and predictive procedures – both basic and innovative – and in applied research. Accurate experimental investigations are needed to validate the numerical calculations. This book contains the edited versions of the papers presented at the Tenth International Conference on Advanced Computational Methods and Experimental Measurements in Heat Transfer and Mass Transfer held in Maribor, Slovenia in July 2008. The objective of this conference series is to provide a forum for presentation and discussion of advanced topics, new approaches and application of advanced computational methods and experimental measurements to heat and mass transfer problems. The contributed papers are grouped in the following appropriate sections to provide better access for readers: Natural and forced convection; Heat exchangers; Advances in computational methods; Heat recovery; Heat transfer; Modelling and experiments.

Download or read book Gas Turbine Heat Transfer and Cooling Technology written by Je-Chin Han and published by Taylor & Francis. This book was released on 2012-11-27 with total page 865 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive reference for engineers and researchers, this second edition focuses on gas turbine heat transfer issues and their associated cooling technologies for aircraft and land-based gas turbines. It provides information on state-of-the-art cooling technologies such as advanced turbine blade film cooling and internal cooling schemes. The book also offers updated experimental methods for gas turbine heat transfer and cooling research, as well as advanced computational models for gas turbine heat transfer and cooling performance predictions. The authors provide suggestions for future research within this technology and includes 800 illustrations to help clarify concepts and instruction.

Download or read book Numerical Study of Louver Cooling Scheme on Gas Turbine Airfoils written by Xuezhi Zhang and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work presents the performance of a louver film-cooling scheme under different operating conditions. The louver cooling scheme consists of a bend by which the coolant going through the flow passage is redirected from vertical to horizontal direction before being injected into the mainstream through an expanded exit. Not only is the momentum of the coolant converted to the mainstream direction, but it is also reduced by the expanded exit before injection. The impingement of the coolant on the blade surface inside the bend also enables further cooling on the targeted surface. The louver cooling scheme was tested under a variety of conditions, from a flat plate to airfoils, from low speed incompressible flows to transonic flows, from a stationary airfoil to a rotating airfoil, and from the leading edge to the middle of an airfoil. Unsteady analysis using a DES (Detached Eddy Simulation) model was also carried out to evaluate its ability to accurately simulate film cooling by comparing with steady state analysis. In general, the louver cooling scheme has been proved to provide enhanced cooling protection to the targeted surface in comparison with other cooling schemes in all conditions tested. At low speed incompressible flow conditions, a higher blowing ratio led to a higher cooling effectiveness. At transonic flow conditions, a moderately higher blowing ratio also proved helpful with a higher cooling effectiveness. Very high blowing ratios, however, proved to be detrimental to the cooling performance since strong detached shock wave structures due to high blowing ratios caused boundary layer separation, rendering the coolant virtually ineffective. The rotation of blade was found to have a significant impact on the level of cooling effectiveness at the leading edge of an airfoil. With regard to the cooling performance, blowing ratio was the dominant factor at low rotational speeds and the rotational speed was the dominant factor at high blowing ratios for circular holes. For the louver scheme as jet liftoff was avoided, effectiveness increased with rotating speed. Results also showed that, unsteady analysis was not significantly more accurate than steady analysis. The unsteady analysis did capture the coolant lateral spreading better, with a high cost of computing, however. Results in this work show that shock waves encountered on transonic airfoils had a significant impact on film cooling effectiveness on any shaped holes. Therefore, experimental data obtained under low speed test should be used with great caution in real design of turbine blade cooling. There are fundamental differences in film cooling between at the leading edge and elsewhere on an airfoil in that a slight incidence shifting due to turbine rotating speed may cause a sudden decrease in cooling effectiveness level at high blowing ratios for circular hole. This could lead to a catastrophic failure if the blade is already in a weak and stressed state. Using of shaped holes with expanded exits may prevent this from happening.