A Second Order Closure Analysis Of Turbulent Diffusion Flames

DOWNLOAD

Download A Second Order Closure Analysis Of Turbulent Diffusion Flames PDF/ePub or read online books in Mobi eBooks. Click Download or Read Online button to get A Second Order Closure Analysis Of Turbulent Diffusion Flames book now. This website allows unlimited access to, at the time of writing, more than 1.5 million titles, including hundreds of thousands of titles in various foreign languages. If the content not found or just blank you must refresh this page

A Second Order Closure Analysis Of Turbulent Diffusion Flames

DOWNLOAD
Author :
language : en
Publisher:
Release Date : 1977

A Second Order Closure Analysis Of Turbulent Diffusion Flames written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 1977 with categories.

Turbulent Mixing In Nonreactive And Reactive Flows

DOWNLOAD
Author : S. Murthy
language : en
Publisher: Springer Science & Business Media
Release Date : 2013-11-11

Turbulent Mixing In Nonreactive And Reactive Flows written by S. Murthy and has been published by Springer Science & Business Media this book supported file pdf, txt, epub, kindle and other format this book has been release on 2013-11-11 with Science categories.

Turbulence, mixing and the mutual interaction of turbulence and chemistry continue to remain perplexing and impregnable in the fron tiers of fluid mechanics. The past ten years have brought enormous advances in computers and computational techniques on the one hand and in measurements and data processing on the other. The impact of such capabilities has led to a revolution both in the understanding of the structure of turbulence as well as in the predictive methods for application in technology. The early ideas on turbulence being an array of complicated phenomena and having some form of reasonably strong coherent struc ture have become well substantiated in recent experimental work. We are still at the very beginning of understanding all of the aspects of such coherence and of the possibilities of incorporating such structure into the analytical models for even those cases where the thin shear layer approximation may be valid. Nevertheless a distinguished body of "eddy chasers" has come into existence. The structure of mixing layers which has been studied for some years in terms of correlations and spectral analysis is also getting better understood. Both probability concepts such as intermittency and conditional sampling as well as the concept of large scale structure and the associated strain seem to indicate possibilities of distinguishing and synthesizing 'engulfment' and molecular mixing.

Evaluation Of Closure Models Of Turbulent Diffusion Flames

DOWNLOAD
Author : G. Kosaly
language : en
Publisher:
Release Date : 2000

Evaluation Of Closure Models Of Turbulent Diffusion Flames written by G. Kosaly and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2000 with Flame categories.

Evaluation Of Closure Models Of Turbulent Diffusion Flames

DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2000

Evaluation Of Closure Models Of Turbulent Diffusion Flames written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2000 with categories.

Modeling methods applied in the field of turbulent combustion were investigated via Direct Numerical Simulations (DNS) and theoretical analysis with an emphasis on subgrid-scale modeling to be applied in Large Eddy Simulations (LES). The DNS results supported the conditional moment closure approximation, refuted the common modeling of differential diffusion effects, raised a suggestion for valid modeling of differential diffusion, resolved outstanding theoretical issues regarding mixing layers, and demonstrated the need for including flamelet/flamelet interactions in the modeling of extinction/reignition events. The DNS methodology was reconfirmed by comparison to the classical laboratory results of Comte-Bellot and Corrsin. A new subgrid-scale model (Large Eddy Laminar Flamelet; LELFM, a quasi-steady model) was established and applied to the prediction of laboratory results in a simulated mixing layer with nitric oxide/ozone reaction. The results support the modeling. New results were derived and confirmed via DNS regarding the subgrid-scale modeling of the filtered mixture fraction, its second moment and dissipation rate.

Evaluation Of Closure Models Of Turbulent Diffusion Flames

DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2000

Evaluation Of Closure Models Of Turbulent Diffusion Flames written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2000 with categories.

Modeling methods applied in the field of turbulent combustion were investigated via Direct Numerical Simulations (DNS) and theoretical analysis with an emphasis on subgrid-scale modeling to be applied in Large Eddy Simulations (LES). The DNS results supported the conditional moment closure approximation, refuted the common modeling of differential diffusion effects, raised a suggestion for valid modeling of differential diffusion, resolved outstanding theoretical issues regarding mixing layers, and demonstrated the need for including flamelet/flamelet interactions in the modeling of extinction/reignition events. The DNS methodology was reconfirmed by comparison to the classical laboratory results of Comte-Bellot and Corrsin. A new subgrid-scale model (Large Eddy Laminar Flamelet; LELFM, a quasi-steady model) was established and applied to the prediction of laboratory results in a simulated mixing layer with nitric oxide/ozone reaction. The results support the modeling. New results were derived and confirmed via DNS regarding the subgrid-scale modeling of the filtered mixture fraction, its second moment and dissipation rate.

Gasdynamics Of Explosions And Reactive Systems

DOWNLOAD
Author : A. K. Oppenheim
language : en
Publisher: Elsevier
Release Date : 2013-10-22

Gasdynamics Of Explosions And Reactive Systems written by A. K. Oppenheim and has been published by Elsevier this book supported file pdf, txt, epub, kindle and other format this book has been release on 2013-10-22 with Science categories.

Gas Dynamics of Explosions and Reactive Systems documents the proceedings of the 6th Colloquium held at the Royal Institute of Technology in Stockholm, Sweden, 22-26 August 1977. The meeting was held under the auspices of the Royal Swedish Academy of Sciences and the International Academy of Astronautics. The scientific program included over one hundred papers. The contributions in this volume are organized into four parts. Part I contains papers on gaseous detonations. It covers topics such as theoretical model of a detonation cell; spherical detonations in hydrocarbon-air mixtures; and shock wave propagation in tubes filled with water foams. Part II presents studies on explosions, such as the detonation of hydrogen azide and propagation of a laser-supported detonation wave. Part III examines condensed phase detonations. It includes papers on the mechanism of the divergent and convergent dark waves originating at the charge boundary in detonating liquid homogeneous explosives with unstable detonation front; and initiation studies in sensitized nitromethane. Part IV presents discussions on turbulent detonations, covering topics such as the computational aspects of turbulent combustion and problems and techniques in turbulent reactive systems.

Scientific And Technical Aerospace Reports

DOWNLOAD
Author :
language : en
Publisher:
Release Date : 1995

Scientific And Technical Aerospace Reports written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 1995 with Aeronautics categories.

An Investigation Of Axisymmetric Buoyant Turbulent Diffusion Flames

DOWNLOAD
Author : S-M. Jeng
language : en
Publisher:
Release Date : 1982

An Investigation Of Axisymmetric Buoyant Turbulent Diffusion Flames written by S-M. Jeng and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 1982 with Fire prevention categories.

This investigation considered measurements of the structure of axisymmetric, buoyant, turbulent diffusion flames in still air. Profiles of mean temperature, mean velocity, velocity fluctuations and total radiant heat flux were completed for methane flames, including careful characterization of burner exit conditions, in order to provide data for the evaluation of models of the process. Preliminary tests also provided mean temperature profiles for propane flames. Test conditions were chosen so that the flow was turbulent near the burner exit while effects of buoyancy were significant over most of the luminous portion of the flames. Both the present measurements and those of other investigators were compared with predictions of a k-E-g differential model, which included effects of buoyancy in the transport equations for turbulence quantities. The results indicated anisotropic effects in regions where buoyancy dominates flow properties suggesting the eventual desirability of multi-stress models for buoyant flames, although extensive recalibration of model constants from a limited data based would be required if this step were taken. Additional measurements and analysis of methane flames are in progress, in order to investigate the flame radiation properties and provide additional data on turbulence properties needed for model development.

A Model Based Closure Approach For Turbulent Combustion Using The One Dimensional Turbulence Model

DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2003

A Model Based Closure Approach For Turbulent Combustion Using The One Dimensional Turbulence Model written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2003 with categories.

A new model-based closure approach for turbulent combustion using the One-Dimensional turbulence model (ODT) is developed and validated in context to a turbulent jet diffusion flame. The interaction of turbulence and chemistry provides interesting finite rate chemistry effects including the phenomena of extinction and re-ignition. The ODT model resolves both spatially and temporally all the scales in a turbulent reaction flow problem, thus, combining the accuracy of a DNS like solver with efficiency by reduction in the number of dimensions. The closure approach is based on identifying the mechanisms responsible for the above mentioned effects and parameterizing the ODT results with a minimum set of scalars transported in the coarse grained solvers like the Reynolds-Averaged Navier-Stokes (RANS) or Large Eddy Simulation (LES). Thus, the closure from ODT is based on a "one-way" coupling between the coarse grained solvers and ODT. Two approaches for closure are developed in the present work with respect to a RANS solver; however, they can be easily extended to LES. The first approach relies on ODT to provide the history effects associated with the geometry, which represent the interactions of turbulence and chemistry, by tabulating scalar statistics (first and second moments) on two parameters measuring, the extent of mixing, the radial mean mixture fraction, and the extent of entrainment, the centerline mean mixture fraction. However, based on the above parameterization, the approach is limited to jet diffusion flame geometry. Furthermore, the closure requires a one to one correspondence between the flames simulated in the coarse grained solver and ODT. As a second approach, the results from ODT are parameterized based on general representative scalars; mixture fraction, which specifies the mixedness of the mixture and temperature, which specifies the reactedness of the mixture. The history effects associated with the flow geometry are provided by the RANS solver in t.

Variable Density Fluid Turbulence

DOWNLOAD
Author : P. Chassaing
language : en
Publisher: Springer Science & Business Media
Release Date : 2013-06-29

Variable Density Fluid Turbulence written by P. Chassaing and has been published by Springer Science & Business Media this book supported file pdf, txt, epub, kindle and other format this book has been release on 2013-06-29 with Science categories.

The first part aims at providing the physical and theoretical framework of the analysis of density variations in fully turbulent flows. Its scope is deliberately educational. In the second part, basic data on dynamical and scalar properties of variable density turbulent flows are presented and discussed, based on experimental data and/or results from direct numerical simulations. This part is rather concerned with a research audience. The last part is more directly devoted to an engineering audience and deals with prediction methods for turbulent flows of variable density fluid. Both first and second order, single point modeling are discussed, with special emphasis on the capability to include specific variable density / compressibility effects.