Download or read book The Influence of Freestream Turbulence and Pressure Gradient on Heat Transfer to Gas Turbine Airfoils written by R.D. Zerkle and published by . This book was released on 1987 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Experimental and Analytical Study of Boundary Layers in Highly Turbulent Free streams written by M. F. Blair and published by . This book was released on 1981 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research was conducted to examine two aspects of boundary layer flow: 1) the influence of free-stream turbulence on zero pressure gradient, full turbulent boundary layer flow; and 2) the combined effects of free-stream turbulence and favorable streamwise pressure gradients on transitional boundary layer flow. Keywords: Convective heat transfer coefficients; Boundary layer transition; Gas turbine airfoils; Boundary layer mean velocity; Experimental data. (edc).
Download or read book Flow Transition in Gas Turbine Airfoil Boundary Layers written by Gregory S. West and published by . This book was released on 1985 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reshotko has suggested that transition may be viewed as the response of a very complex three-dimensional nonlinear oscillator (the laminar boundary layer) to a random and often statistically nonuniform forcing function (the disturbances). The first objective of this study concerns the phenomenon of flow transition in boundary layers on turbine airfoils--from the onset of turbulence to the transition completion. Transition studies, though fundamental to fluid mechanics, are unique in gas turbine cascades because of the compounding factors that act not in individual isolation, but as a collective group and that constitute by-pass mechanisms not amenable to linear analyses from a mathematical point of view. The second objective is to evolve an engineering method to account for surface roughness effects on heat transfer and turbulent boundary layer analyses, which have heretofore been studied in fragments. Transition prediction in gas turbine boundary layer flows is critical in assessing the cooling requirements for gas turbine vanes and blades. This report summarizes the classical, fundamental findings in transition prediction for simplified geometrics and discusses empirical rules currently in use for gas turbine environments. Keywords: Airfoil boundary layer transition.
Download or read book The Combined Effects of Freestream Turbulence Pressure Gradients and Surface Roughness on Turbine Aerodynamics written by Christine P. Ellering and published by . This book was released on 2002-03-01 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work used scaled facsimiles of real turbine blade surfaces to characterize correlations between turbine blade roughness, freestream turbulence, pressure gradients and skin friction (Cf). Addition of roughness caused Cf to increase: up to 300% for the roughest surface. Addition of freestream turbulence resulted in 125% increase for the same surface. The combined effects showed increases up to 380%. Although decreasing roughness, freestream turbulence, and Reynolds number resulted in less dramatic results, it was concluded that the Cf increases due to combined effects were consistently higher than their corresponding sum of the parts. The combined effects of roughness and pressure gradients yielded inconclusive results, however, limited observations seem to corroborate the trends seen during zero pressure gradient tests.
Download or read book The Effects of Inlet Turbulence and Rotor stator Interactions on the Aerodynamics and Heat Transfer of a Large scale Rotating Turbine Model Volume 1 written by Robert P. Dring and published by . This book was released on 1987 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of High Intensity Large Scale Freestream Combustor Turbulence on Heat Transfer in Transonic Turbine Blades written by and published by . This book was released on 2003 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: The influence of freestream turbulence representative of the flow downstream of a modem gas turbine combustor and the first stage vane on turbine blade heat transfer has been measured and analytically modeled in a linear, transonic turbine cascade. Measurements were performed on a high turning, transonic turbine blade. The facility is capable of heated flow with inlet total temperature of 120 degrees C and inlet total pressure of 10 psig. The Reynolds number based on blade chord and exit conditions (5x10(exp 6)) and the inlet and exit Mach numbers (0.4 and 1.2, respectively) are representative of conditions in a modem gas turbine engine. High intensity, large length-scale freestream turbulence was generated using a passive turbulence-generating grid to simulate the turbulence generated in modem combustors after it has passed through the first stage vane row. The grid produced freestream turbulence with intensity of approximately 10-12% and an integral length scale of 2 cm near the entrance of the cascade passages, which is believed to be representative of the core flow entering a first stage gas turbine rotor blade row. Mean heat transfer results showed an increase in heat transfer coefficient of approximately 8% on the suction surface of the blade, with increases on the pressure surface on the order of two times higher than on the suction surface (approximately 17%). This corresponds to increases in blade surface temperature of 5- 10%, which can significantly reduce the life of a turbine blade. The heat transfer data were compared with correlations from published literature with good agreement.
Download or read book Turbulent Spot Characterization and the Modeling of Transitional Heat Transfer in Turbines written by and published by . This book was released on 2001 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optimum design of gas turbine blades depends on accurate prediction of boundary layer transition. The purpose of this research is to obtain more information on the generation. propagation and coalescence of turbulent spots in a transitional boundary layer and examine the effects of free stream turbulence pressure gradient and cross flow. Experimental data from this study may be used to improve existing CFD models, allowing designers to make more accurate predictions of transitional heat transfer in turbines.
Download or read book Flow and Heat Transfer Experiments in the Turbine Airfoil endwall Region written by Jin Taek Chung and published by . This book was released on 1992 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of the Effect of Free Stream Turbulence on the Heat Transfer to Turbine Airfoil written by Richard D. Lander and published by . This book was released on 1969 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: This program was conducted to evaluate the effects of gas stream turbulence, originating in a modern turbojet engine-type burner, on the rate of heat transfer to the leading edge and suction surfaces of two different turbine airfoils. While meeting this objective, the procedures that are necessary to calibrate and utilize uncooled hot film anemometers to measure free stream turbulence in high pressure-high temperature gas streams were studied. In addition, an investigation was made of the feasibility of using cooled hot film anemometer probes, designed to operate in extremely high temperature environments, to measure free stream turbulence in modern turbojet burner discharge environments. (Author).
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 Progress in Modeling of Laminar to Turbulent Transition on Turbine Vanes and Blades written by and published by . This book was released on 1996 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transition in Turbines written by and published by . This book was released on 1985 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Heat Transfer in Gas Turbine Engines written by American Society of Mechanical Engineers. Winter Annual Meeting and published by . This book was released on 1989 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Heat Transfer in Gas Turbine Engines and Three dimensional Flows written by American Society of Mechanical Engineers. Winter Annual Meeting and published by . This book was released on 1988 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Two equation Low Reynolds number Turbulence Modeling of Transitional Boundary Layer Flows Characteristic of Gas Turbine Blades written by Rodney C. Schmidt and published by . This book was released on 1987 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
