Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Flamlet Based Analysis Of Non Equilibrium Effects And No Formation In Turbulent Hydrogen Diffusion Flames
Download Flamlet Based Analysis Of Non Equilibrium Effects And No Formation In Turbulent Hydrogen Diffusion Flames full books in PDF, epub, and Kindle. Read online Flamlet Based Analysis Of Non Equilibrium Effects And No Formation In Turbulent Hydrogen Diffusion Flames ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Flamlet-based Analysis of Non-equilibrium Effects and NO-formation in Turbulent Hydrogen Diffusion Flames by : J. P. H. Sanders
Download or read book Flamlet-based Analysis of Non-equilibrium Effects and NO-formation in Turbulent Hydrogen Diffusion Flames written by J. P. H. Sanders and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis A Scaling Study of NO Formation in Turbulent Diffusion Flames of Hydrogen Burning in Air by : George A. Lavoie
Download or read book A Scaling Study of NO Formation in Turbulent Diffusion Flames of Hydrogen Burning in Air written by George A. Lavoie and published by . This book was released on 1975* with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author :National Aeronautics and Space Administration (NASA) Publisher :Createspace Independent Publishing Platform ISBN 13 :9781723057441 Total Pages :158 pages Book Rating :4.0/5 (574 download)
Book Synopsis Flamelet Model Application for Non-Premixed Turbulent Combustion by : National Aeronautics and Space Administration (NASA)
Download or read book Flamelet Model Application for Non-Premixed Turbulent Combustion written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-17 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: The current Final Report contains results of the study which was performed in Scientific Research Center 'ECOLEN' (Moscow, Russia). The study concerns the development and verification of non-expensive approach for modeling of supersonic turbulent diffusion flames based on flamelet consideration of the chemistry/turbulence interaction (FL approach). Research work included: development of the approach and CFD tests of the flamelet model for supersonic jet flames; development of the simplified procedure for solution of the flamelet equations based on partial equilibrium chemistry assumption; study of the flame ignition/extinction predictions provided by flamelet model. The performed investigation demonstrated that FL approach allowed to describe satisfactory main features of supersonic H 2/air jet flames. Model demonstrated also high capabilities for reduction of the computational expenses in CFD modeling of the supersonic flames taking into account detailed oxidation chemistry. However, some disadvantages and restrictions of the existing version of approach were found in this study. They were: (1) inaccuracy in predictions of the passive scalar statistics by our turbulence model for one of the considered test cases; and (2) applicability of the available version of the flamelet model to flames without large ignition delay distance only. Based on the results of the performed investigation, we formulated and submitted to the National Aeronautics and Space Administration our Project Proposal for the next step research directed toward further improvement of the FL approach. Secundov, A. and Bezgin, L. and Buriko, Yu. and Guskov, O. and Kopchenov, V. and Laskin, I. and Lomkov, K. and Tshepin, S. and Volkov, D. and Zaitsev, S. Unspecified Center TURBULENT COMBUSTION; TURBULENT DIFFUSION; DIFFUSION FLAMES; SUPERSONIC JET FLOW; COMPUTATIONAL FLUID DYNAMICS; TURBULENCE MODELS; CHEMICAL REACTIONS; IGNITION; EXTINCTION; GAS MIXTURES; AIR JETS; OXIDATION; DIFFERENTIAL EQUATIONS; ...
Book Synopsis Turbulent Combustion by : Norbert Peters
Download or read book Turbulent Combustion written by Norbert Peters and published by Cambridge University Press. This book was released on 2000-08-15 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: The combustion of fossil fuels remains a key technology for the foreseeable future. It is therefore important that we understand the mechanisms of combustion and, in particular, the role of turbulence within this process. Combustion always takes place within a turbulent flow field for two reasons: turbulence increases the mixing process and enhances combustion, but at the same time combustion releases heat which generates flow instability through buoyancy, thus enhancing the transition to turbulence. The four chapters of this book present a thorough introduction to the field of turbulent combustion. After an overview of modeling approaches, the three remaining chapters consider the three distinct cases of premixed, non-premixed, and partially premixed combustion, respectively. This book will be of value to researchers and students of engineering and applied mathematics by demonstrating the current theories of turbulent combustion within a unified presentation of the field.
Book Synopsis Analysis of Turbulent Free Jet Hydrogen-air Diffusion Flames with Finite Chemical Reaction Rates by : J. P. Sislian
Download or read book Analysis of Turbulent Free Jet Hydrogen-air Diffusion Flames with Finite Chemical Reaction Rates written by J. P. Sislian and published by . This book was released on 1978 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis International Aerospace Abstracts by :
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1997 with total page 940 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Properties of Large Turbulent Hydrogen/Air Diffusion Flames by : Harold S. Pergament
Download or read book Properties of Large Turbulent Hydrogen/Air Diffusion Flames written by Harold S. Pergament and published by . This book was released on 1977 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: The prediction of IR radiation from large, turbulent H2/air diffusion flames requires a detailed analysis of flame properties, including the effects of buoyancy. This report gives the methodology employed for analyzing such flames and the results of calculations on large flames. These (and subsequent) results have been used as input to the IR radiation calculations on the C-1 stack discussed in Part 2 of this final report. The model discussed herein treats the axisymmetric turbulent mixing of coflowing streams, including nonequilibrium chemistry, employing an eddy viscosity formulation. Comparisons are made between model predictions and the nonbuoyant laboratory H2/air flame data. It is shown that centerline temperatures and species mole fractions can be predicted to good accuracy. However, the calculated rate of radial transport of energy and mass is greater than that measured in the laboratory experiments. The results of a series of parametric calculations on buoyant flames and comparisons with buoyant flame length data show that: flame properties scale with nondimensional distance for Froude numbers (Fr) greater than about 1,000,000, buoyancy significantly affects temperature decay rates downstream of the location of maximum temperature (after all the H2 has burned), and the predicted influence of Fr on buoyant flame lengths is consistent with the available data.
Book Synopsis Journal of Thermophysics and Heat Transfer by :
Download or read book Journal of Thermophysics and Heat Transfer written by and published by . This book was released on 1996 with total page 1390 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.
Book Synopsis Nonequilibrium Anomalies in the Development of Diffusion Flames by : P. M. Chung
Download or read book Nonequilibrium Anomalies in the Development of Diffusion Flames written by P. M. Chung and published by . This book was released on 1965 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of diffusion flame is analyzed for the stagnation mixing layer created by a jet of fuel injected into the oncoming stream of oxidant at the stagnation region of blunt body. From the analysis, the conditions which distinguish the simple and multiple transitions, from each other, between frozen and equilibrium chemical states were clarified. Though the actual numerical results were obtained for the stagnation mixing layer geometry, the basic findings of the analysis should hold for other diffusion flames also. (Author).
Book Synopsis Study of Finite-Rate Chemistry Effects on Turbulent Jet Diffusion Flames and Non-homogeneous Autoigntion Using the One-Dimensional Turbulence Model by :
Download or read book Study of Finite-Rate Chemistry Effects on Turbulent Jet Diffusion Flames and Non-homogeneous Autoigntion Using the One-Dimensional Turbulence Model written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In current study Numerical simulation of turbulent combustion process is approached using One Dimensional Turbulence (ODT) model. The ODT model is based on the coupling of molecular processes (reaction and diffusion) with turbulent transport in a spatially- and temporally-resolved fashion over a one-dimensional domain. The domain corresponds to a transverse (or radial) direction; while, the transient evolution of the thermo-chemical scalars on the 1D domain represents the spatial evolution downstream of the jet inlet. The linear-eddy approach for modeling molecular mixing in turbulent flow involves stochastic simulation on a 1D domain with sufficient resolution to predict all relevant physical length scales properly. Firstly ODT is carried out to predict the hydrogen and air jet diffusion flame with helium dilution in the fuel. The comparison with existing experimental data was made for the numerical result of ODT simulation of jet diffusion flames in both conditional means and rms of scalars of measurements and computational results. Another application of ODT was made in present work to verify the capability of prediction of autoignition (self-ignition) of one of free shear layer flow -- jet diffusion flow. Different range of pressure and Reynolds number are set to identify the effects of turbulence intensity and mixture properties on the self-ignition chemistry. Autoignition delay time was studied based on these different conditions. At the same time the ability of the prediction of mixture temperature and species mass fraction profile were tested. A principle numerical result is expected and discussed. Conditional pdf and progress variable were used to analyze the computational result of ODT. Analysis was focus on the temperature growth and the mass fraction distribution of intermediate species and product.
Book Synopsis Modelling Detailed-Chemistry Effects on Turbulent Diffusion Flames Using a Parallel Solution-Adaptive Scheme by : Pradeep Kumar Jha
Download or read book Modelling Detailed-Chemistry Effects on Turbulent Diffusion Flames Using a Parallel Solution-Adaptive Scheme written by Pradeep Kumar Jha and published by . This book was released on 2011 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: Capturing the effects of detailed-chemistry on turbulent combustion processes is a central challenge faced by the numerical combustion community. However, the inherent complexity and non-linear nature of both turbulence and chemistry require that combustion models rely heavily on engineering approximations to remain computationally tractable. This thesis proposes a computationally efficient algorithm for modelling detailed-chemistry effects in turbulent diffusion flames and numerically predicting the associated flame properties. The cornerstone of this combustion modelling tool is the use of parallel Adaptive Mesh Refinement (AMR) scheme with the recently proposed Flame Prolongation of Intrinsic low-dimensional manifold (FPI) tabulated-chemistry approach for modelling complex chemistry. The effect of turbulence on the mean chemistry is incorporated using a Presumed Conditional Moment (PCM) approach based on a beta-probability density function (PDF). The two-equation k-w turbulence model is used for modelling the effects of the unresolved turbulence on the mean flow field. The finite-rate of methane-air combustion is represented here by using the GRI-Mech 3.0 scheme. This detailed mechanism is used to build the FPI tables. A state of the art numerical scheme based on a parallel block-based solution-adaptive algorithm has been developed to solve the Favre-averaged Navier-Stokes (FANS) and other governing partial-differential equations using a second-order accurate, fully-coupled finite-volume formulation on body-fitted, multi-block, quadrilateral/hexahedral mesh for two-dimensional and three-dimensional flow geometries, respectively. A standard fourth-order Runge-Kutta time-marching scheme is used for time-accurate temporal discretizations. Numerical predictions of three different diffusion flames configurations are considered in the present work: a laminar counter-flow flame; a laminar co-flow diffusion flame; and a Sydney bluff-body turbulent reacting flow. Comparisons are made between the predicted results of the present FPI scheme and Steady Laminar Flamelet Model (SLFM) approach for diffusion flames. The effects of grid resolution on the predicted overall flame solutions are also assessed. Other non-reacting flows have also been considered to further validate other aspects of the numerical scheme. The present schemes predict results which are in good agreement with published experimental results and reduces the computational cost involved in modelling turbulent diffusion flames significantly, both in terms of storage and processing time.
Book Synopsis Turbulent Reactive Flows by : R. Borghi
Download or read book Turbulent Reactive Flows written by R. Borghi and published by Springer Science & Business Media. This book was released on 2013-03-08 with total page 958 pages. Available in PDF, EPUB and Kindle. Book excerpt: Turbulent reactive flows are of common occurrance in combustion engineering, chemical reactor technology and various types of engines producing power and thrust utilizing chemical and nuclear fuels. Pollutant formation and dispersion in the atmospheric environment and in rivers, lakes and ocean also involve interactions between turbulence, chemical reactivity and heat and mass transfer processes. Considerable advances have occurred over the past twenty years in the understanding, analysis, measurement, prediction and control of turbulent reactive flows. Two main contributors to such advances are improvements in instrumentation and spectacular growth in computation: hardware, sciences and skills and data processing software, each leading to developments in others. Turbulence presents several features that are situation-specific. Both for that reason and a number of others, it is yet difficult to visualize a so-called solution of the turbulence problem or even a generalized approach to the problem. It appears that recognition of patterns and structures in turbulent flow and their study based on considerations of stability, interactions, chaos and fractal character may be opening up an avenue of research that may be leading to a generalized approach to classification and analysis and, possibly, prediction of specific processes in the flowfield. Predictions for engineering use, on the other hand, can be foreseen for sometime to come to depend upon modeling of selected features of turbulence at various levels of sophistication dictated by perceived need and available capability.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1991 with total page 1380 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Advanced Combustion Science by : Tsuneo Someya
Download or read book Advanced Combustion Science written by Tsuneo Someya and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: Non-uniform combustion, as encountered in diesel and gas turbine engines, furnaces, and boilers, is responsible for the conversion of fossil fuel to energy and also for the corresponding formation of pollutants. In spite of great research efforts in the past, the mechanism of non-uniform combustion has remained less explored than that of other combustion types, since it consists of many, mostly transient processes which influence each other. In view of this background, a group research project, "Exploration of Combustion Mechanism", was established to explore the mechanism of combustion, especially that of diffusive combustion, and also to find efficient ways to control the combustion process for better utilization of fuel and the reduction of pollutant emission. The group research was started, after preparatory activity of 2 years, in April 1988, for a period of 3 years, as a project with a Grant-in-Aid for Scientific Research of Priority Area subsidized by the Ministry of Education, Science and Culture of Japan. The entire group of 43 members was set up as an organizing committee of 13 members, and five research groups, consisting of 36 members. The research groups were: (1) Steady combustion, (2) Unsteady spray combustion, (3) Control of combustion, (4) Chemistry of combustion, and (5) Effects of fuels. At the beginning of the project it was agreed that we should pursue the mechanism of combustion from a scientific viewpoint, namely, the target of the project was to obtain the fundamentals, or "know why", rather than "know how" of combustion.
Book Synopsis Molecular Transport Effects in Turbulent Diffusion Flames at Moderate Reynolds Number by : R. W. Bilger
Download or read book Molecular Transport Effects in Turbulent Diffusion Flames at Moderate Reynolds Number written by R. W. Bilger and published by . This book was released on 1981 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: In flames molecular diffusivities are enhanced by the high temperatures and can be of the same order as turbulent diffusivities in flames of moderate Reynolds number. A perturbation analysis is used to quantify effects in a hydrogen/air diffusion flame which arise from differential molecular diffusivities. The analysis uses perturbations about the equal diffusivity, adiabatic, equilibrium theory commonly used and yields solutions for the average and higher moments for the departures in normalized element mass fractions and enthalpy. The results are compared with the laser-Raman measurements of Drake et al. in a relatively low Reynolds number flame. Generally the agreement is excellent. (Author).
Book Synopsis Turbulent Premixed Flames by : Nedunchezhian Swaminathan
Download or read book Turbulent Premixed Flames written by Nedunchezhian Swaminathan and published by Cambridge University Press. This book was released on 2011-04-25 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: A work on turbulent premixed combustion is important because of increased concern about the environmental impact of combustion and the search for new combustion concepts and technologies. An improved understanding of lean fuel turbulent premixed flames must play a central role in the fundamental science of these new concepts. Lean premixed flames have the potential to offer ultra-low emission levels, but they are notoriously susceptible to combustion oscillations. Thus, sophisticated control measures are inevitably required. The editors' intent is to set out the modeling aspects in the field of turbulent premixed combustion. Good progress has been made on this topic, and this cohesive volume contains contributions from international experts on various subtopics of the lean premixed flame problem.
Author :National Aeronautics and Space Administration (NASA) Publisher :Createspace Independent Publishing Platform ISBN 13 :9781725049772 Total Pages :26 pages Book Rating :4.0/5 (497 download)
Book Synopsis A Study of Hydrogen Diffusion Flames Using PDF Turbulence Model by : National Aeronautics and Space Administration (NASA)
Download or read book A Study of Hydrogen Diffusion Flames Using PDF Turbulence Model written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-08-10 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: The application of probability density function (pdf) turbulence models is addressed. For the purpose of accurate prediction of turbulent combustion, an algorithm that combines a conventional computational fluid dynamic (CFD) flow solver with the Monte Carlo simulation of the pdf evolution equation was developed. The algorithm was validated using experimental data for a heated turbulent plane jet. The study of H2-F2 diffusion flames was carried out using this algorithm. Numerical results compared favorably with experimental data. The computations show that the flame center shifts as the equivalence ratio changes, and that for the same equivalence ratio, similarity solutions for flames exist. Hsu, Andrew T. Unspecified Center NAS2-5266...
