Download or read book Turbulent Heat Transfer Investigation Turbulence Length Scales and Turbine Heat Transfer written by and published by . This book was released on 1996 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: This experiment was designed to study the effects of turbulent length scales on turbine blade heat transfer in a steady state cascade wind tunnel. Turbine blade heat transfer is of interest due to the beneficial effects engine performance that can arise from improvements in turbine blade cooling and design. Turbulence in this experiment was generated by means of passive grids in the upstream flow. This experiment uses a steady state liquid crystal in combination with resistance heating to measure heat transfer. The liquid crystals provide surface temperature data and the resistance heating in the blade can be computed from measured currents to determine heat transfer. When combined with flow data taken with a hot film this allows for conclusions on the effects of length scales on heat transfer to be made. This experiment showed that the turbine blade heat transfer exhibited the trends already investigated for turbulence intensity, namely an increase in heat transfer with increased turbulence, the forward movement of boundary layer transition and the elimination of pressure side spanwise variations. Comparison of the two different length scales at the same turbulence intensity showed that the length scale evidenced no affect on transition location or post-transition heat transfer. However, pre-transition heat transfer was significantly increased as the integral length scale decreased from 2.78 to 0.51. This demonstrates that smaller more compact eddies in the turbulent flow have a more significant impact on increasing heat transfer than do larger eddies of the same intensity.
Download or read book Modelling and Simulation of Turbulent Heat Transfer written by B. Sundén and published by WIT Press. This book was released on 2005-02-21 with total page 361 pages. Available in PDF, EPUB and Kindle. Book excerpt: Providing invaluable information for both graduate researchers and R & D engineers in industry and consultancy, this book focuses on the modelling and simulation of fluid flow and thermal transport phenomena in turbulent convective flows. Its overall objective is to present state-of-the-art knowledge in order to predict turbulent heat transfer processes in fundamental and idealized flows as well as in engineering applications. The chapters, which are invited contributions from some of the most prominent scientists in this field, cover a wide range of topics and follow a unified outline and presentation to aid accessibility.
Download or read book Application of Turbulence Modeling to Predict Surface Heat Transfer in Stagnation Flow Region of Circular Cylinder written by Chi-Rong Wang and published by . This book was released on 1987 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Research Program for Improving Heat Transfer Prediction for the Laminar to Turbulent Transition Region of Turbine Vanes blades written by Frederick F. Simon and published by . This book was released on 1993 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Augmentation of Stagnation Region Heat Transfer Due to Turbulence From a DLN Can Combustor written by G. James VanFossen and published by . This book was released on 2000 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Heat Transfer with High Intensity Large Scale Turbulence written by Stanford University. Thermosciences Division. Thermosciences Division and published by . This book was released on 1990 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Measurement and Control of Heat Transfer in Steady and Unsteady Turbulent Separated Flow written by and published by . This book was released on 1995 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: The turbulence structure of convective heat transfer was studied experimentally in complex three- dimensional and separated turbulent boundary layers. Three test cases whose fluid dynamics have been well documented were examined. In case 1, time resolved surface heat transfer was measured in the nose region of a wing-body junction formed by a wing and a flat plate. Mean, statistical and spectral characteristics of the surface heat transfer are reported. The effects of wing shape were investigated by measuring the surface heat transfer in the nose region of a modified NACA 0020, a streamlined cylinder shape and NACA 0015. The effectiveness of a flow control device to reduce surface heat transfer is reported. In case 2, simultaneous surface heat flux and temperature profiles were measured at 11 locations in the spatially-developing pressure-driven three-dimensional turbulent boundary layer upstream of the wing-body junction. In case 3, simultaneous surface heat flux and temperature profiles were measured at 18 stream-wise locations in a mean 2-dimensional adverse-pressure gradient separating turbulent boundary layer. Mean, statistical and spectral heat flux and temperature data are reported. Mean ejection frequencies, turbulence length scales, inclination angles of the turbulence structure. and coherency between the inner and outer regions of the flow were examined from these results. Several useful correlations between surface heat transfer and velocity are reported.
Download or read book Turbulence Modelling Approaches written by Konstantin Volkov and published by BoD – Books on Demand. This book was released on 2017-07-26 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accurate prediction of turbulent flows remains a challenging task despite considerable work in this area and the acceptance of CFD as a design tool. The quality of the CFD calculations of the flows in engineering applications strongly depends on the proper prediction of turbulence phenomena. Investigations of flow instability, heat transfer, skin friction, secondary flows, flow separation, and reattachment effects demand a reliable modelling and simulation of the turbulence, reliable methods, accurate programming, and robust working practices. The current scientific status of simulation of turbulent flows as well as some advances in computational techniques and practical applications of turbulence research is reviewed and considered in the book.
Download or read book Numerical Prediction of Flow Heat Transfer Turbulence and Combustion written by D. Brian Spalding and published by Elsevier. This book was released on 2015-07-14 with total page 445 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical Prediction of Flow, Heat Transfer, Turbulence and Combustion: Selected Works of Professor D. Brian Spalding focuses on the many contributions of Professor Spalding on thermodynamics. This compilation of his works is done to honor the professor on the occasion of his 60th birthday. Relatively, the works contained in this book are selected to highlight the genius of Professor Spalding in this field of interest. The book presents various research on combustion, heat transfer, turbulence, and flows. His thinking on separated flows paved the way for the multi-dimensional modeling of turbulence. Arguments on the universality of the models of turbulence and the problems that are associated with combustion engineering are clarified. The text notes the importance of combustion science as well as the problems associated with it. Mathematical computations are also presented in determining turbulent flows in different environments, including on curved pipes, curved ducts, and rotating ducts. These calculations are presented to further strengthen the claims of Professor Spalding in this discipline. The book is a great find for those who are interested in studying thermodynamics.
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 Microscales of Turbulence written by Vedat S Arpaci and published by CRC Press. This book was released on 1998-01-16 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph presents the microscales of complex (buoyant, thermocapillary, two-phase, reacting, radiating, pulsating, etc.) turbulent flows and interprets heat and mass transfer correlations in terms of these scales. The author introduces a general methodology for the development of microscales for complex turbulent flows. Then he provides, by these scales, a fundamental interpretation for a number of momentum, heat, and mass transfer correlations which are assumed to be empirical. Lastly, he develops correlations in terms of these scales for environmentally and/or technologically important problems related to buoyancy driven flows, pulsating flows, diffusion flows, fires, etc.
Download or read book Heat Transfer Augmentation in Turbulent Flows written by Antanas Pedišius and published by . This book was released on 1995 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: Turbulent flow is the most common form of motion of liquids and gases playing the role of the heat-transfer medium in thermal systems. The complexity of turbulent flow and the importance of hydrodynamics and heat transfer in practice inspired continuing research for methods of efficient heat augmentation by the Lithuanian Energy Institute. The solution of this problem was directly linked with the determination of the reaction of flow in the boundary layer to the effect of various factors and heat transfer rate under given conditions. The investigated factors included elevated degree of turbulence of the external flow as well as strong acceleration and turbulization of flow near the wall by surface roughness. The material in this volume shows that it is possible to control the efficiency of turbulent transfer when the vortical structure of the turbulent flow is known.
Download or read book Modeling of the Heat Transfer in Bypass Transitional Boundary layer Flows written by Frederick F. Simon and published by . This book was released on 1991 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of Turbulence Length Scale on Heat Transfer written by Roger W. Moss and published by . This book was released on 1992 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Engineering Turbulence Modelling and Experiments 4 written by D. Laurence and published by Elsevier. This book was released on 1999-04-14 with total page 975 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings contain the papers presented at the 4th International Symposium on Engineering Turbulence Modelling and Measurements held at Ajaccio, Corsica, France from 24-26 May 1999. It follows three previous conferences on the topic of engineering turbulence modelling and measurements. The purpose of this series of symposia is to provide a forum for presenting and discussing new developments in the area of turbulence modelling and measurements, with particular emphasis on engineering-related problems. Turbulence is still one of the key issues in tackling engineering flow problems. As powerful computers and accurate numerical methods are now available for solving the flow equations, and since engineering applications nearly always involve turbulence effects, the reliability of CFD analysis depends more and more on the performance of the turbulence models. Successful simulation of turbulence requires the understanding of the complex physical phenomena involved and suitable models for describing the turbulent momentum, heat and mass transfer. For the understanding of turbulence phenomena, experiments are indispensable, but they are equally important for providing data for the development and testing of turbulence models and hence for CFD software validation.
