Download or read book A Numerical Model for Turbulent Channel Flow Under the Influence of Rotation written by Jerry L. Fuqua and published by . This book was released on 1985 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Direct Numerical Simulation Lie Group Analysis and Modeling of a Turbulent Channel Flow with Wall normal Rotation written by Amirfarhang Mehdizadeh and published by . This book was released on 2010 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Influence of Rotation on Flow in a Long Rectangular Channel written by R. M. Halleen and published by . This book was released on 1967 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: An investigation is reported of the flow regimes and structures in flow through a rectangular channel rotating about an axis perpendicular to the relative velocity vector of the narrow walls of the channel. Flow regimes for the wall layers of the leading and trailing surfaces as functions of the Reynolds Number and a nondimensional rotation parameter are delineated. Flow regime data were obtained primarily from wall-slot dye injection and photography. Mean velocity profiles, wall shear, and reduced pressure across the channel are also given. For no rotation, the flow had a fully developed turbulent mean velocity profile for all cases investigated. As the speed of rotation is increased, important changes in the wall structures, shear, and mean velocity profiles are observed on both walls. (Author).
Download or read book Simulation and Modeling of Turbulent Flows written by Thomas B. Gatski and published by Oxford University Press. This book was released on 1996-07-11 with total page 329 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides students and researchers in fluid engineering with an up-to-date overview of turbulent flow research in the areas of simulation and modeling. A key element of the book is the systematic, rational development of turbulence closure models and related aspects of modern turbulent flow theory and prediction. Starting with a review of the spectral dynamics of homogenous and inhomogeneous turbulent flows, succeeding chapters deal with numerical simulation techniques, renormalization group methods and turbulent closure modeling. Each chapter is authored by recognized leaders in their respective fields, and each provides a thorough and cohesive treatment of the subject.
Download or read book Statistical Theory and Modeling for Turbulent Flows written by P. A. Durbin and published by John Wiley & Sons. This book was released on 2011-06-28 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: Providing a comprehensive grounding in the subject of turbulence, Statistical Theory and Modeling for Turbulent Flows develops both the physical insight and the mathematical framework needed to understand turbulent flow. Its scope enables the reader to become a knowledgeable user of turbulence models; it develops analytical tools for developers of predictive tools. Thoroughly revised and updated, this second edition includes a new fourth section covering DNS (direct numerical simulation), LES (large eddy simulation), DES (detached eddy simulation) and numerical aspects of eddy resolving simulation. In addition to its role as a guide for students, Statistical Theory and Modeling for Turbulent Flows also is a valuable reference for practicing engineers and scientists in computational and experimental fluid dynamics, who would like to broaden their understanding of fundamental issues in turbulence and how they relate to turbulence model implementation. Provides an excellent foundation to the fundamental theoretical concepts in turbulence. Features new and heavily revised material, including an entire new section on eddy resolving simulation. Includes new material on modeling laminar to turbulent transition. Written for students and practitioners in aeronautical and mechanical engineering, applied mathematics and the physical sciences. Accompanied by a website housing solutions to the problems within the book.
Download or read book Large Eddy Simulation of Compressible Turbulent Channel and Annular Pipe Flows with System and Wall Rotations written by Joon Sang Lee and published by . This book was released on 2004 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: The compressible filtered Navier-Stokes equations were solved using a second order accurate finite volume method with low Mach number preconditioning. A dynamic subgrid-scale stress model accounted for the subgrid-scale turbulence. The study focused on the effects of buoyancy and rotation on the structure of turbulence and transport processes including heat transfer. Several different physical arrangements were studied as outlined below. The effects of buoyancy were first studied in a vertical channel using large eddy simulation (LES). The walls were maintained at constant temperatures, one heated and the other cooled. Results showed that aiding and opposing buoyancy forces emerge near the heated and cooled walls, respectively. In the aiding flow, the turbulent intensities and heat transfer were suppressed at large values of Grashof number. In the opposing flow, however, turbulence was enhanced with increased velocity fluctuations. Another buoyancy study considered turbulent flow in a vertically oriented annulus. Isoflux wall boundary conditions with low and high heating were imposed on the inner wall while the outer wall was adiabatic. The results showed that the strong heating and buoyancy force caused distortions of the flow structure resulting in reduction of turbulent intensities, shear stress, and turbulent heat flux, particularly near the heated wall. Flow in an annular pipe with and without an outer wall rotation about its axis was first investigated at moderate Reynolds numbers. When the outer pipe wall was rotated, a significant reduction of turbulent kinetic energy was realized near the rotating wall. Secondly, a large eddy simulation has been performed to investigate the effect of swirl on the heat and momentum transfer in an annular pipe flow with a rotating inner wall. The simulations indicated that the Nusselt number and the wall friction coefficient increased with increasing rotation speed of the wall. It was also observed that the axial velocity profile became flattened and turbulent intensities were enhanced due to swirl. As a part of the study of rotation effects, a large eddy simulation of a rotating ribbed channel flow with the heat transfer was investigated. The rotation axis was parallel to the spanwise direction of the parallel plate channel. Uniform heat flux was applied to the channel for two rates of rotation. The results showed that near the stable (leading) side, the turbulent intensities and heat transfer were suppressed, but turbulence was enhanced with increasing shear stress and turbulent kinetic energy near the unstable (trailing) side.
Download or read book Hydrodynamic and Magnetohydrodynamic Turbulent Flows written by A. Yoshizawa and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt: TUrbulence modeling encounters mixed evaluation concerning its impor tance. In engineering flow, the Reynolds number is often very high, and the direct numerical simulation (DNS) based on the resolution of all spatial scales in a flow is beyond the capability of a computer available at present and in the foreseeable near future. The spatial scale of energetic parts of a turbulent flow is much larger than the energy dissipative counterpart, and they have large influence on the transport processes of momentum, heat, matters, etc. The primary subject of turbulence modeling is the proper es timate of these transport processes on the basis of a bold approximation to the energy-dissipation one. In the engineering community, the turbulence modeling is highly evaluated as a mathematical tool indispensable for the analysis of real-world turbulent flow. In the physics community, attention is paid to the study of small-scale components of turbulent flow linked with the energy-dissipation process, and much less interest is shown in the foregoing transport processes in real-world flow. This research tendency is closely related to the general belief that universal properties of turbulence can be found in small-scale phenomena. Such a study has really contributed much to the construction of statistical theoretical approaches to turbulence. The estrangement between the physics community and the turbulence modeling is further enhanced by the fact that the latter is founded on a weak theoretical basis, compared with the study of small-scale turbulence.
Download or read book Turbulent Flows written by Jean Piquet and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 767 pages. Available in PDF, EPUB and Kindle. Book excerpt: obtained are still severely limited to low Reynolds numbers (about only one decade better than direct numerical simulations), and the interpretation of such calculations for complex, curved geometries is still unclear. It is evident that a lot of work (and a very significant increase in available computing power) is required before such methods can be adopted in daily's engineering practice. I hope to l"Cport on all these topics in a near future. The book is divided into six chapters, each· chapter in subchapters, sections and subsections. The first part is introduced by Chapter 1 which summarizes the equations of fluid mechanies, it is developed in C~apters 2 to 4 devoted to the construction of turbulence models. What has been called "engineering methods" is considered in Chapter 2 where the Reynolds averaged equations al"C established and the closure problem studied (§1-3). A first detailed study of homogeneous turbulent flows follows (§4). It includes a review of available experimental data and their modeling. The eddy viscosity concept is analyzed in §5 with the l"Csulting ~alar-transport equation models such as the famous K-e model. Reynolds stl"Css models (Chapter 4) require a preliminary consideration of two-point turbulence concepts which are developed in Chapter 3 devoted to homogeneous turbulence. We review the two-point moments of velocity fields and their spectral transforms (§ 1), their general dynamics (§2) with the particular case of homogeneous, isotropie turbulence (§3) whel"C the so-called Kolmogorov's assumptions are discussed at length.
Download or read book Turbulence and Interactions written by Michel Deville and published by Springer Science & Business Media. This book was released on 2010-09-28 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains six keynote lectures and 44 contributed papers of the TI 2009 conference that was held in Saint-Luce, La Martinique, May 31-June 5, 2009. These lectures address the latest developments in direct numerical simulations, large eddy simulations, compressible turbulence, coherent structures, droplets, two-phase flows, etc. The present monograph is a snapshot of the state-of-the-art in the field of turbulence with a broad view on theory, experiments and numerical simulations.
Download or read book Numerical Simulation of Unsteady Flows and Transition to Turbulence written by O. Pironneau and published by Cambridge University Press. This book was released on 1992-07-31 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: The workshop concentrated on the following turbulence test cases: T1 Boundary layer in an S-shaped duct; T2 Periodic array of cylinders in a channel; T3 Transition in a boundary layer under the influence of free-stream turbulence; T4 & T5: Axisymmetric confined jet flows.
Download or read book Application of a Two Layer Near Wall Model to Fully Developed and Rotating Channel Turbulent Flows written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-08-20 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: The two-layer near wall approach in combination with the k-epsilon model was applied to rotating flows. Validation studies show that the conventional length scales have to be modified to account for rotating effects. Guided by the Lam and Bremhorst's low Reynolds number model with the rotation-corrected k-epsilon model, a new set of length scales formulation is proposed. The developments and validations of the current model are reported. A fully elliptic numerical method developed to solve the two-dimensional Reynolds-averaged Navier-Stokes equations is employed for the computational study. Chen, C. P. and Guo, K. L. Unspecified Center NAS8-36955...
Download or read book Turbulent Shear Flows 9 written by Franz Durst and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: The inaugural Symposium on Turbulent Shear Flows was held at The Pennsylvania State University in 1977. Thereafter the locations for the biennial symposium have alternated between the USA and Europe. However, the ninth Symposium on Turbu lent Shear Flows was awarded to Japan in recognition of the strong support researchers of the Pacific Rim countries have given previous symposia. The University of Kyoto was the host institution and the meeting was held in the Inter national Conference Hall. The Local Arrangements Committee did a superb job scheduling traditional Japanese dinners and arranging visits to the many cultural treasures in the Kyoto region. The meeting attracted more than 260 offers of papers. Thirty-three sessions were scheduled to accommodate the 138 papers accepted for oral presentation. In addition a poster session was scheduled on each of the three days to accommodate a total of 42 poster presentations. From the presentations at the symposium 24 have been selected for inclusion in this volume. The authors of these papers have revised them taking into consideration comments made during their oral presentation and recommendations made by the Editors. Four subject areas are identified, namely closures and fundamentals, free flows, wall flows, and combustion and recirculating flows. Eminent authorities have prepared introductory articles fot each topic to put the individual contributions in context with each other and with related research.
Download or read book Turbulent Flows written by G. Biswas and published by CRC Press. This book was released on 2002 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book allows readers to tackle the challenges of turbulent flow problems with confidence. It covers the fundamentals of turbulence, various modeling approaches, and experimental studies. The fundamentals section includes isotropic turbulence and anistropic turbulence, turbulent flow dynamics, free shear layers, turbulent boundary layers and plumes. The modeling section focuses on topics such as eddy viscosity models, standard K-E Models, Direct Numerical Stimulation, Large Eddy Simulation, and their applications. The measurement of turbulent fluctuations experiments in isothermal and stratified turbulent flows are explored in the experimental methods section. Special topics include modeling of near wall turbulent flows, compressible turbulent flows, and more.
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:
Download or read book Engineering Turbulence Modelling and Experiments 6 written by Wolfgang Rodi and published by Elsevier. This book was released on 2005-05-05 with total page 1011 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the world renowned ERCOFTAC (International Symposium on Engineering Turbulence Modelling and Measurements). The proceedings include papers dealing with the following areas of turbulence: · Eddy-viscosity and second-order RANS models · Direct and large-eddy simulations and deductions for conventional modelling · Measurement and visualization techniques, experimental studies · Turbulence control · Transition and effects of curvature, rotation and buoyancy on turbulence · Aero-acoustics · Heat and mass transfer and chemically reacting flows · Compressible flows, shock phenomena · Two-phase flows · Applications in aerospace engineering, turbomachinery and reciprocating engines, industrial aerodynamics and wind engineering, and selected chemical engineering problems Turbulence remains one of the key issues in tackling engineering flow problems. These problems are solved more and more by CFD analysis, the reliability of which depends strongly on the performance of the turbulence models employed. 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. As in other fields of Science, in the rapidly developing discipline of turbulence, swift progress can be achieved only by keeping up to date with recent advances all over the world and by exchanging ideas with colleagues active in related fields.
Download or read book Applied mechanics reviews written by and published by . This book was released on 1948 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book CFD Applications in Nuclear Engineering written by Wenxi Tian and published by Frontiers Media SA. This book was released on 2023-08-21 with total page 219 pages. Available in PDF, EPUB and Kindle. Book excerpt: High fidelity nuclear reactor thermal hydraulic simulations are a hot research topic in the development of nuclear engineering technology. The three-dimensional Computational Fluid Dynamics (CFD) and Computational Multi-phase Fluid Dynamics (CMFD) methods have attracted significant attention in predicting single-phase and multi-phase flows under steady-state or transient scenarios in the field of nuclear reactor engineering. Compared with three-dimensional thermal hydraulic methods, the traditional one-dimensional system analysis method contains inherent defects in the required accuracy and spatial resolution for a number of important nuclear reactor thermal-hydraulic phenomena. At present the CFD method has been widely adopted in the nuclear industry, across both light water reactors and liquid metal cooled fast reactors, providing an effective solution for complex issues of thermal hydraulic analysis. However, the CFD method employs empirical models for turbulence simulation, heat transfer, multi-phase interaction and chemical reactions. Such models must be validated before they can be used with confidence in nuclear reactor applications. In addition, user practice guidelines play a critical role in achieving reliable results from CFD simulations.
