Download or read book Heat Transfer Measurements in Rotating Turbine Blade Cooling Channel Configurations Using the Transient Thermochromic Liquid Crystal Technique written by Christian Waidmann and published by . This book was released on 2021 with total page 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 Gas Turbine Film Cooling and Heat Transfer Measurements Using a Transient Liquid Crystal Technique written by Srinath Varadarajan Ekkad and published by . This book was released on 1995 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurements of Heat Transfer Flow and Pressures in a Simulated Turbine Blade Internal Cooling Passage written by Louis M. Russell and published by . This book was released on 1997 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental study was made to obtain quantitative information on heat transfer, flow, and pressure distribution in a branched duct test section that had several significant features of an internal cooling passage of a turbine blade. The objective of this study was to generate a set of experimental data that could be used for validation of computer codes that would be used to model internal cooling. Surface heat transfer coefficients and entrance flow conditions were measured at nominal entrance Reynolds numbers of 45 000, 335 000, and 726 000. Heat transfer data were obtained by using a steady-state technique in which an Inconel heater sheet is attached to the surface and coated with liquid crystals. Visual and quantitative flow-field data from particle image velocimetry measurements for a plane at midchannel height for a Reynolds number of 45 000 were also obtained. The flow was seeded with polystyrene particles and illuminated by a laser light sheet. Pressure distribution measurements were made both on the surface with discrete holes and in the flow field with a total pressure probe. The flow-field measurements yielded flow-field velocities at selected locations. A relatively new method, pressure sensitive paint, was also used to measure surface pressure distribution. The pressure paint data obtained at Reynolds numbers of 335 000 and 726 000 compared well with the more standard method of measuring pressures by using discrete holes.

Download or read book Emerging Topics in Heat Transfer written by Qiuwang Wang and published by WIT Press. This book was released on 2013-11-06 with total page 417 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presented in ten edited chapters this book encompasses important emerging topics in heat transfer equipment, particularly heat exchangers. The chapters have all been selected by invitation only. Advances in high temperature equipment and small scale devices continue to be important as the involved heat transfer and related phenomena are often complex in nature and different mechanisms like heat conduction, convection, turbulence, thermal radiation and phase change as well as chemical reactions may occur simultaneously. The book treats various operating problems, like fouling, and highlights applications in heat exchangers and gas turbine cooling. In engineering design and development, reliable and accurate computational methods are required to replace or complement expensive and time consuming experimental trial and error work. Tremendous advancements in knowledge and competence have been achieved during recent years due to improved computational solution methods for non-linear partial differential equations, turbulence modelling advancement and developments of computers and computing algorithms to achieve efficient and rapid simulations. The chapters of the book thoroughly present such advancement in a variety of applications.

Download or read book Advances in Heat Transfer written by and published by Academic Press. This book was released on 1993-07-22 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Heat Transfer

Download or read book Heat Transfer Experiments in the Internal Cooling Passages of a Cooled Radial Turbine Rotor written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-18 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental study was conducted (1) to experimentally measure, assess and analyze the heat transfer within the internal cooling configuration of a radial turbine rotor blade and (2) to obtain heat transfer data to evaluate and improve computational fluid dynamics (CFD) procedures and turbulent transport models of internal coolant flows. A 1.15 times scale model of the coolant passages within the NASA LERC High Temperature Radial Turbine was designed, fabricated of Lucite and instrumented for transient beat transfer tests using thin film surface thermocouples and liquid crystals to indicate temperatures. Transient heat transfer tests were conducted for Reynolds numbers of one-fourth, one-half, and equal to the operating Reynolds number for the NASA Turbine. Tests were conducted for stationary and rotating conditions with rotation numbers in the range occurring in the NASA Turbine. Results from the experiments showed the heat transfer characteristics within the coolant passage were affected by rotation. In general, the heat transfer increased and decreased on the sides of the straight radial passages with rotation as previously reported from NASA-HOST-sponsored experiments. The heat transfer in the tri-passage axial flow region adjacent to the blade exit was relatively unaffected by rotation. However, the heat transfer on one surface, in the transitional region between the radial inflow passage and axial, constant radius passages, decreased to approximately 20 percent of the values without rotation. Comparisons with previous 3-D numerical studies indicated regions where the heat transfer characteristics agreed and disagreed with the present experiment. Johnson, B. V. and Wagner, J. H. Unspecified Center TURBINE BLADES; INTERNAL FLOW; RADIAL FLOW; THERMOCOUPLES; THIN FILMS; COOLING; TRANSIENT HEATING; TEMPERATURE MEASUREMENT; TURBULENT FLOW; REYNOLDS NUMBER; SCALE MODELS; LIQUID CRYSTALS; POLYMETHYL METHACRYLATE; VORTICES; COMPUTATIONAL FLUID DYNAMICS...

Download or read book Energy Research Abstracts written by and published by . This book was released on 1987 with total page 1316 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Heat transfer measurements for a film cooled turbine vane cascade written by Douglas R. Thurman and published by . This book was released on 2008 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Application of the Transient Heat Transfer Measurement Technique Using Thermochromic Liquid Crystals in Networks of Intersecting Circular Passages written by Anika Steurer and published by . This book was released on 2020 with total page 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 1993 with total page 1014 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Endwall Heat Transfer Measurements in a Transonic Turbine Cascade written by and published by . This book was released on 1996 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Turbine blade endwall heat transfer measurements are given for a range of Reynolds and Mach numbers. Data were obtained for Reynolds numbers based on inlet conditions of 0.5 and 1.0 x 10(exp 6), for isentropic exit Mach numbers of 1.0 and 1.3, and for freestream turbulence intensities of 0.25% and 7.0%. Tests were conducted in a linear cascade at the NASA Lewis Transonic Turbine Blade Cascade Facility. The test article was a turbine rotor with 136 deg of turning and an axial chord of 12.7 cm. The large scale allowed for very detailed measurements of both flow field and surface phenomena. The intent of the work is to provide benchmark quality data for CFD code and model verification. The flow field in the cascade is highly three-dimensional as a result of thick boundary layers at the test section inlet. Endwall heat transfer data were obtained using a steady-state liquid crystal technique.

Download or read book Experimental Heat Transfer and Bulk Air Temperature Measurements for a Multipass Internal Cooling Model with Ribs and Bleed written by Douglas R. Thurman and published by . This book was released on 2000 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental study was made to obtain heat transfer and air temperature data for a simple 3-leg serpentine test section that simulates a turbine blade internal cooling passage with trip strips and bleed holes. The objectives were to investigate the interaction of ribs and various bleed conditions on internal cooling and to gain a better understanding of bulk air temperature in an internal passage. Steady state heat transfer measurements were obtained using a transient technique with thermochromic liquid crystals. Trip strips were attached to one wall of the test section and were located either between or near the bleed holes. The bleed holes, used for film cooling, were metered to simulate the effect of external pressure on the turbine blade. Heat transfer enhancement was found to be greater for ribs near bleed holes compared to ribs between holes, and both configurations were affected slightly by bleed rates upstream. Air temperature measurements were taken at discreet locations along one leg of the model. Average bulk air temperatures were found to remain fairly constant along one leg of the model.

Download or read book Heat Transfer for a Stationary Serpentine Passage Using a Transient Thermochromatic Liquid Crystal Paint Technique written by Timothy Robert Lawler and published by . This book was released on 2015 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: As demand for greater and greater fuel efficiency is felt in the airline industry, there is a need to decrease specific fuel consumption of gas turbine engines. One method for improving specific fuel consumption is elevating the overall operating temperature of the engine, resulting in higher efficiency. Over time, the turbine inlet temperature of modern gas turbine engines has increased to above the working temperature of the materials used to construct the high-pressure turbine stages. To maintain safety, performance, and maintainability of these parts, active cooling techniques have been developed for the high-pressure turbine. Among these methods is internal cooling, wherein core flow is bled from the high-pressure compressor and is forced through serpentine passages within the blades of the high-pressure turbine. As this practice reduces the mass flow of air through the combustor, it reduces overall efficiency. Therefore, the amount of air bled from the compressor must be optimized. A stationary three passage serpentine is presented to represent the internal cooling passages of the high-pressure turbine blades. Heat transfer measurements are provided for a square aspect ratio, 1:1, geometry representative of some gas turbine engines and comparable to existing datasets. Departing from previous experiments, this project focused on employing transient thermal liquid crystals (TLC) to gain a fully two-dimensional temperature distribution throughout the test section. Turbulators are mounted at 45° skew to the flow direction with a fixed pitch to height ratio (e/P) of ten and a height to hydraulic diameter ratio (e/D_h) of 0.058.

Download or read book Measurements of the Heat Transfer Coefficient Distribution on Flat and Ribbed Surfaces with Interrupted Heating Using Thermochromic Liquid Crystals written by Jason D. Wolf and published by . This book was released on 1998 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of the heat transfer coefficient distribution on flat and ribbed surfaces with interrupted heating are presented. One application of this type of thermal boundary condition is the cooling of surface mounted modules in electronic packaging. Heating occurs at the modules, with no heating between the modules. The heat transfer measurements in the present study are made using the heated-coating method with a thermochromic liquid crystal (TLC). The "coating" is vacuum-deposited gold on a plastic sheet, which is mounted on a Styrofoam surface. The gold film is electrically heated to produce the surface heat flux. The surface temperature is measured by capturing color images of the TLC, using the hue technique. These surface temperature plots are transformed into heat transfer coefficient distributions on the surface of the models. Interrupted heating on the flat surface is obtained by heating strips perpendicular to the freestream flow, with insulated spaces between the strips. The ribbed surface is heated on the top of the ribs only, with insulated unheated cavities in-between. The results show that, as expected, the local heat transfer coefficient is higher on the heated strips of the flat surface interrupted heating case, than would be present at the same locations with a uniform heat flux. The interruption of the thermal boundary layer at each unheated section allows it to "reset", thereby causing the higher heat transfer on the following heated section. The ribbed model shows a slight increase in heat transfer on the ribs above that of the flat plate interrupted heating model. The cavities appear to introduce mixing that causes this change. The increase in h due to the ribs is small, however, when compared to the effect of the interrupted heating.

Download or read book A New Technique for Dynamic Flow Visualization and Heat Transfer Measurement Using Liquid Crystal Thermography written by Agustin David Ochoa and published by . This book was released on 2004 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Impingement Cooling and Heat Transfer Measurement Using Transient Liquid Crystal Technique written by Yizhe Huang and published by . This book was released on 1996 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: