Download or read book Application of Conjugate Heat Transfer Cht Methodology for Computation of Heat Transfer on a Turbine Blade written by Jatin Gupta and published by . This book was released on 2008 with total page 55 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The conventional thermal design method of cooled turbine blade consists of independent decoupled analysis of the blade external flow, the blade internal flow and the analysis of heat conduction in the blade itself. To make such a calculation, proper interface conditions need to be applied. In the absence of film cooling, a proper treatment would require computation of heat transfer coefficient by computing heat flux for an assumed wall temperature. This yields an invariant h to the wall and free stream temperature that is consistent with the coupled calculation. When film-cooling is involved the decoupled method does not yield a heat transfer coefficient that is invariant and a coupled analysis becomes necessary. Fast computers have made possible this analysis of coupling the conduction to both the internal and external flow. Such a single coupled numerical simulation is known as conjugate heat transfer simulation. The conjugate heat transfer methodology has been employed to predict the flow and thermal properties, including the metal temperature, of a particular NASA turbine vane. The three-dimensional turbine vane is subjected to hot mainstream flow and is cooled with air flowing radially through ten cooling channels. The passage flow and heat transfer, internal coolant flow and heat transfer, and conduction within the metal are solved simultaneously using conjugate heat transfer methodology. Unlike the decoupled approach, the conjugate simulation does not require thermal boundary conditions on the turbine walls. It is believed that turbulence has a large influence on heat transfer and hence in the present study, a modified k-omega model by Wilcox was used for the external flow and it was compared to Wilcox's standard k-omega model to see if the new model provided any improvement in predicting the heat transfer on the blade surface. Results here have shown that, for the present geometry, the standard model is still much better in predicting temperature and hence the heat transfer over the blade surface than the modified model. A thermal barrier coating (TBC) "system" is used to thermally protect turbine engine blades and vanes from the hot gases in gas turbine engines. The overall results from this study, including turbulence modeling and the use of TBC, are encouraging and indicate that conjugate heat transfer simulation with proper turbulence closure is a viable tool in turbine heat transfer analysis and cooling design.
Download or read book Conjugate Heat Transfer on a Gas Turbine Blade written by Santiago Salazar and published by . This book was released on 2010 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clearances between gas turbine casings and rotating blades is of quite importance on turbo machines since a significant loss of efficiency can occur if the clearances are not predicted accordingly. The radial thermal growths of the blade may be over or under predicted if poor assumptions are made on calculating the metal temperatures of the surfaces exposed to the fluid. The external surface of the blade is exposed to hot gas temperatures and it is internally cooled with air coming from the compressor. This cold air enters the radial channels at the root of the blade and then exists at the tip. To obtain close to realistic metal temperatures on the blade, the Conjugate Heat Transfer (CHT) approach would be utilized in this research. The radial thermal growth of the blade would be then compared to the initial guess. This work focuses on the interaction between the external boundary conditions obtained from the commercial Computational Fluid Dynamics software package CFX, the internal boundary conditions along the channels from a 1D flow solver proprietary to Siemens Energy, and the 3D metal temperatures and deformation of the blade predicted using the commercial Solid Mechanics software package ANSYS. An iterative technique to solve CHT problems is demonstrated and discussed. The results of this work help to highlight the importance of CHT in predicting metal temperatures and the implications it has in other aspect of the gas turbine design such as the tip clearances.
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 A Pragmatic Method for Matching Conjugate Heat Transfer Predictions of High Pressure Turbine Blades with Thermal Paint Tests written by Jonathan Hilgert and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Pragmatic Method for Matching Conjugate Heat Transfer Predictions of High Pressure Turbine Blades with Thermal Paint Tests written by Jonathan Hilgert and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Introduction to Optimization Methods and Tools for Multidisciplinary Design in Aeronautics and Turbomachinery written by Jacques Periaux and published by . This book was released on 2008 with total page 624 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 Constrained Aerodynamic and Heat Transfer Optimization of Gas Turbine Blades Using an Adjoint Approach written by Seyyed Arash Mousavi and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "This research work presents an adjoint approach to optimize the aero-thermalproperties of gas turbine blades. The flow solver is a Reynolds-Averaged Navier-Stokes code applicable to structured grids. The flow governing equations are discretizedusing a second-order finite-volume scheme and for artificial dissipation, theJameson-Schmidt-Turkel (JST) scheme is applied in order to accurately capture theflow discontinuities. The code uses a five-stage modified Runge-Kutta explicit temporaldiscretisation and utilizes the multigrid method, residual smoothing and thelocal time stepping for convergence acceleration.A loosely coupled conjugate heat transfer (CHT) method is applied to considerthe effect of the internal convective cooling and obtain the fluid-solid interface temperatureat the blade surface. A finite-element solver is developed to solve the energyequation in the solid domain and the governing equation is solved by implementingthe weak-Galerkin finite-element discretization scheme where an unstructured lineartriangular mesh is adopted for the solution domain. The temperature at the solid andfluid interface is computed through an iterative exchange of the boundary conditionsacross the interface using the Flux Forward Temperature Back (FFTB) method. Forexternally cooled blades, a source term injection model is implemented to model theeffect of external cooling on the blade surface heat transfer.The optimization procedure is gradient-based and the blade shape optimizationis accomplished through SNOPT, a sequential-quadratic programming package thatis capable of automatically handling the linear and/or non-linear flow and geometric constraints. To efficiently calculate the gradients, a continuous adjoint method isemployed and in order to be consistent with the flow boundary condition, a characteristicbased approach is utilized in developing the adjoint boundary conditions.The flow solver is validated for several benchmark turbomachinery cascades.The optimization procedure is applied to several inviscid and viscous turbine andcompressor blades to enhance the aerodynamic and/or thermal performance. Thedeveloped optimization algorithm is demonstrated to be efficient in terms of computationaltime and accuracy for the optimization of two-dimensional turbomachinerycases where it provides promising results in reducing the desired objective functionswhile respecting the imposed flow and geometric constraints." --
Download or read book Radiation Heat Transfer Modelling with Computational Fluid Dynamics written by Yehuda Sinai and published by CRC Press. This book was released on 2022-06-21 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book serves as a preliminary reference for the principles of thermal radiation and its modelling in computational fluid dynamics (CFD) simulations. Radiation Heat Transfer Modelling with Computational Fluid Dynamics covers strategies and processes for synthesizing radiation with CFD setups, computational techniques for solving the radiative transfer equation, the strengths and weaknesses thereof, boundary and initial conditions and relevant guidelines. Describing the strategic planning of a typical project, the book includes the spectroscopic properties of gases, some particulates and porous media. FEATURES Fills a gap between existing CFD and thermal radiation textbooks and elaborates on some aspects of user manuals. Aims at (1) CFD practitioners who are newcomers to thermal radiation and are looking for a preliminary introduction thereon and (2) modellers familiar with thermal radiation looking for a precursory introduction to CFD. The book is tilted somewhat towards the first group. Provides guidelines for choosing the right model, the strategic planning of the modelling and its implementation. Outlines the pitfalls of some solution techniques. Describes how radiation is included in the variety of boundary condition types offered by CFD codes. Helps to develop the practical skills required to plan, implement and interpret thermal radiation within the typical CFD code. Addresses a wide variety of physical circumstances in which thermal radiation plays a role. Offers ample references for readers searching for additional details. Includes several examples of practical applications, including fire, a utility boiler and car headlights in cold environments. This book is intended for researchers and professionals who wish to simulate problems that involve fluid flow and heat transfer with thermal radiation.
Download or read book Experimental and Applied Mechanics Volume 4 written by Carlos E. Ventura and published by Springer Science & Business Media. This book was released on 2012-11-29 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental and Applied Mechanics, Volume 4: Proceedings of the 2012 Annual Conference on Experimental and Applied Mechanics, the fourth volume of seven from the Conference, brings together 54 contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Experimental and Applied Mechanics, including papers on: Fracture & Fatigue Microscale & Microstructural Effects in Fatigue & Fracture Material Applications Composite Characterization Using Digital Image Correlation Techniques Multi-Scale Simulation and Testing of Composites Residual Stress Inverse Problems/Hybrid Methods Nano-Composites Microstructure Material Characterization Modeling and Uncertainty Quantification Impact Behavior of Composites
Download or read book Determination of Gas to blade Convection Heat transfer Coefficients on a Forced convection Water cooled Single stage Aluminum Turbine written by John C. Freche and published by . This book was released on 1951 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Noise Control Reduction and Cancellation Solutions in Engineering written by Daniela Siano and published by BoD – Books on Demand. This book was released on 2012-03-02 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Noise has various effects on comfort, performance, and human health. For this reason, noise control plays an increasingly central role in the development of modern industrial and engineering applications. Nowadays, the noise control problem excites and attracts the attention of a great number of scientists in different disciplines. Indeed, noise control has a wide variety of applications in manufacturing, industrial operations, and consumer products. The main purpose of this book, organized in 13 chapters, is to present a comprehensive overview of recent advances in noise control and its applications in different research fields. The authors provide a range of practical applications of current and past noise control strategies in different real engineering problems. It is well addressed to researchers and engineers who have specific knowledge in acoustic problems. I would like to thank all the authors who accepted my invitation and agreed to share their work and experiences.
Download or read book Journal of Thermophysics and Heat Transfer written by and published by . This book was released on 2000 with total page 1190 pages. Available in PDF, EPUB and Kindle. Book excerpt: This journal is devoted to the advancement of the science and technology of thermophysics and heat transfer through the dissemination of original research papers disclosing new technical knowledge and exploratory developments and applications based on new knowledge. It publishes papers that deal with the properties and mechanisms involved in thermal energy transfer and storage in gases, liquids, and solids or combinations thereof. These studies include conductive, convective, and radiative modes alone or in combination and the effects of the environment.
Download or read book Advanced Computational Methods and Design for Greener Aviation written by Tero Tuovinen and published by Springer Nature. This book was released on with total page 289 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Coupled FVM BEM Approach to Conjugate Heat Transfer in Turbine Blades written by Hongjun Li and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Using Conjugate Heat Transfer to Assess the Cooling Performance on a Turbine Endwall written by Amy Mensch and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Advancements in cooling for applications such as gas turbines components require improved understanding of the complex heat transfer mechanisms and the interactions between those mechanisms. Turbine designers often rely on multiple thermal protection techniques, including internal cooling, external film cooling, and thermal barrier coatings to efficiently cool components and limit the use of coolant. Traditionally, the effectiveness of such cooling technologies is quantified by considering the convection and conduction heat transfer mechanisms separately. The current research considers the combined effects of both internal and external cooling in a single experiment or simulation using a conjugate heat transfer approach.The geometry used for this study is a turbine blade endwall, which is influenced by three-dimensional vortices generated by the passage flow. The experiments and computational simulations include impingement and film cooling as well as conduction through the endwall. Appropriate geometric and flow parameters are properly scaled to ensure engine relevant dimensionless temperatures are obtained. The overall effectiveness, which is a scaled wall temperature, is compared for multiple cases, including different cooling configurations and the implementation of endwall contouring, thermal barrier coatings, and contaminant deposition. The measurements showed that impingement cooling was a larger contributor to the combined overall effectiveness compared to film cooling. The area-averaged contoured endwall overall effectiveness was similar to the flat endwall despite local differences in film cooling effectiveness and impingement effectiveness. The thermal barrier coating significantly increased overall effectiveness by reducing the external heat transfer. Contaminant deposition increased surface roughness, which increased external heat transfer to the endwall.Computational simulations of conjugate heat transfer and time-resolved flowfield measurements helped to understand the complex mechanisms acting together to generate the overall cooling effectiveness. The predicted endwall temperature fields show the three-dimensional temperature gradients present in conjugate heat transfer. The flat and contoured endwall flowfield measurements show that film cooling jets and the passage vortex interact to generate the secondary flowfield impacting endwall heat transfer. Several recommendations for mitigating increased heat transfer and optimizing the cooling performance for gas turbine endwalls are given.
Download or read book 8th International Conference on Turbochargers and Turbocharging written by IMechE and published by Elsevier. This book was released on 2016-06-15 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: Building on the success of an established series of successful conferences held every four years since 1978, 8th International Conference on Turbochargers and Turbocharging presents the latest technologies relating to engine pressure charging systems from international industry and academic experts in the field, covering new developments in compressors and novel intake systems; Improved models for cycle simulation; Electro boost systems; Industry trends and requirements; Turbines and mechanical aspects such as thermomechanical analysis, dynamics, and axial load capacity. Discusses the latest technologies relating to engine pressure charging systems Looks at mechanical aspects such as thermomechanical analysis, dynamics, and axial load capacity
