Download or read book Modeling Engine Spray and Combustion Processes written by Gunnar Stiesch and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: The utilization of mathematical models to numerically describe the performance of internal combustion engines is of great significance in the development of new and improved engines. Today, such simulation models can already be viewed as standard tools, and their importance is likely to increase further as available com puter power is expected to increase and the predictive quality of the models is constantly enhanced. This book describes and discusses the most widely used mathematical models for in-cylinder spray and combustion processes, which are the most important subprocesses affecting engine fuel consumption and pollutant emissions. The relevant thermodynamic, fluid dynamic and chemical principles are summarized, and then the application of these principles to the in-cylinder processes is ex plained. Different modeling approaches for the each subprocesses are compared and discussed with respect to the governing model assumptions and simplifica tions. Conclusions are drawn as to which model approach is appropriate for a specific type of problem in the development process of an engine. Hence, this book may serve both as a graduate level textbook for combustion engineering stu dents and as a reference for professionals employed in the field of combustion en gine modeling. The research necessary for this book was carried out during my employment as a postdoctoral scientist at the Institute of Technical Combustion (ITV) at the Uni versity of Hannover, Germany and at the Engine Research Center (ERC) at the University of Wisconsin-Madison, USA.
Download or read book Advanced Spray and Combustion Modelling written by Ahmed Abed Al-Kadhem Majhool and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The thesis presents work across three different subjects of investigations into the modelling of spray development and its interaction with non-reactive and reactive flow. The first part of this research is aimed to create a new and robust family of convective scheme to capture the interface between the dispersed and the carrier phases without the need to build up the interface boundary. The selection of Weighted Average Flux (WAF) scheme is due to this scheme being designed to deal with random flux scheme which is second-order accurate in space and time. The convective flux in each cell face utilizes the WAF scheme blended with Switching Technique for Advection and Capturing of Surfaces (STACS) scheme for high resolution flux limiters. However in the next step, the high resolution scheme is blended with the scheme to provide the sharpness and boundedness of the interface by using switching strategy. The proposed scheme is tested on capturing the spray edges in modelling hollow cone type sprays without need to reconstruct two-phase interface. A test comparison between TVD scheme and WAF scheme using the same flux limiter on convective flow on hollow cone spray is presented. Results show that the WAF scheme gives better prediction than the TVD scheme. The only way to check the accuracy of the presented models are evaluations according to physical droplets behaviour and its interaction with air. In the second part, due to the effect of evaporation the temperature profile in the released fuel vapour has been proposed. The underlying equation utilizes transported vapour mass fraction. It can be used along with the solution of heat transfer inside a sphere. After applying boundary conditions, the equation can provide a solution of existing conditions at liquid-gas interface undergoing evaporation and it is put in a form similar to well-known one-third rule equation. The resulting equation is quadratic type that gives an accurate prediction for the thermo-physical properties due to the non-linear relation between measured properties and temperature. Comparisons are made with one-third rule where both equations are implemented in simulating hollow cone spray under evaporation conditions. The results show the presumed equation performs better than one-third rule in all comparisons. The third part of this research is about a conceptual model for turbulent spray combustion for two combustion regimes that has been proposed and tested for n-heptane solid cone spray type injected into a high-pressure, high-temperature open reactor by comparing to the available experimental data and to results obtained using two well known combustion models named the Combined Combustion Model (CCM) and the unsteady two-dimensional conditional moment closure (CMC) model. A single-zone intermittent beta-two equation turbulent model is suggested to characterise the Lumped zone. This model can handle both unburned and burned zones. Intermittency theory is used to account for the spatially non-uniform distribution of viscous dissipation. The model suggests that the Lumped zone can be identified by using the concept of Tennekes and Kuo-Corrsion of isotropic turbulence that suggests that dissipative eddies are most probably formed as vortex tubes with a diameter of the order of Kolmogorov length scale and a space of the order of Taylor length scale. Due to the complexity of mixture motion in the combustion chamber, there exist coherent turbulent small scale structures containing highly dissipative vortices. The small size eddies play an important role in extinguishing a diffusion spray flame and have an effect on the combustion reaction at molecular scale because small scales turbulence increase heat transfer due to the dissipation. A common hypothesis in constructing part of the model is if the Kolmogorov length scale is larger than the turbulent flame thickness. The Lumped strategy benefits from capturing small reactive scales information provided by numerics to improve the modelling and understand the exact implementation of the underlying chemical hypothesis. The Lumped rate is estimated from the ratio of the turbulent diffusion to reaction flame thickness. Three different initial gas temperature test cases are implemented in simulations. Lumped spray combustion model shows a very good agreement with available experimental data concerning auto-ignition delay points.
Download or read book Advanced Models for Turbulent Spray and Combustion Simulations written by Abolfazl Irannejad and published by . This book was released on 2013 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Models for Turbulent Spray and Combustion Simulations written by Abolfazl Irannejad and published by LAP Lambert Academic Publishing. This book was released on 2015-08-27 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: A high-fidelity two-phase large eddy simulation (LES)/filtered mass density function (FMDF) model is developed and used for detailed simulations of turbulent spray breakup, evaporation and combustion. The spray is simulated with Lagrangian droplet transport, stochastic breakup, wake, collision/coalescence and finite rate heat and mass transfer submodels. The spray/droplet model is used together with a compressible LES gas flow model for numerical simulations of high pressure liquid jets sprayed into a high temperature and pressure gas chamber. The developed spray LES model is coupled with the two-phase FMDF model for simulation of high speed spray combustion. The FMDF is a subgrid-scale probability density function (PDF) model for LES of turbulent reacting fows and is obtained by the solution of a set of stochastic differential equations by a Lagrangian Monte Carlo method. Complex skeletal kinetics models are used for the chemical reaction together with in situ adaptive tabulation (ISAT) and chemistry workload balancing for efficient parallel computations.
Download or read book Modeling and Simulation of Turbulent Combustion written by Santanu De and published by Springer. This book was released on 2017-12-12 with total page 663 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a comprehensive review of state-of-the-art models for turbulent combustion, with special emphasis on the theory, development and applications of combustion models in practical combustion systems. It simplifies the complex multi-scale and nonlinear interaction between chemistry and turbulence to allow a broader audience to understand the modeling and numerical simulations of turbulent combustion, which remains at the forefront of research due to its industrial relevance. Further, the book provides a holistic view by covering a diverse range of basic and advanced topics—from the fundamentals of turbulence–chemistry interactions, role of high-performance computing in combustion simulations, and optimization and reduction techniques for chemical kinetics, to state-of-the-art modeling strategies for turbulent premixed and nonpremixed combustion and their applications in engineering contexts.
Download or read book Advanced Modelling of Spray Combustion Processes in Airbreathing Propulsion Combustors written by T.L. Jiang and published by . This book was released on 1987 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Current Status of Spray Combustion Modelling written by William A. Sirignano and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Coarse Grained Simulation and Turbulent Mixing written by Fenando F. Grinstein and published by Cambridge University Press. This book was released on 2016-06-30 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reviews our current understanding of the subject. For graduate students and researchers in computational fluid dynamics and turbulence.
Download or read book Advanced Turbulent Combustion Physics and Applications written by N. Swaminathan and published by Cambridge University Press. This book was released on 2022-01-06 with total page 485 pages. Available in PDF, EPUB and Kindle. Book excerpt: Explore a thorough overview of the current knowledge, developments and outstanding challenges in turbulent combustion and application.
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.
Download or read book NUMERICAL MODELING OF SPRAY COMBUSTION WITH AN ADVANCED VOF METHOD NASA CR 201118 JAN 28 1997 written by United States. National Aeronautics and Space Administration and published by . This book was released on 1998* with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flow and Combustion in Advanced Gas Turbine Combustors written by Johannes Janicka and published by Springer Science & Business Media. This book was released on 2012-10-29 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: With regard to both the environmental sustainability and operating efficiency demands, modern combustion research has to face two main objectives, the optimization of combustion efficiency and the reduction of pollutants. This book reports on the combustion research activities carried out within the Collaborative Research Center (SFB) 568 “Flow and Combustion in Future Gas Turbine Combustion Chambers” funded by the German Research Foundation (DFG). This aimed at designing a completely integrated modeling and numerical simulation of the occurring very complex, coupled and interacting physico-chemical processes, such as turbulent heat and mass transport, single or multi-phase flows phenomena, chemical reactions/combustion and radiation, able to support the development of advanced gas turbine chamber concepts
Download or read book Experiments and Numerical Simulations of Turbulent Combustion of Diluted Sprays written by Bart Merci and published by Springer Science & Business Media. This book was released on 2014-03-27 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reflects the results of the 2nd and 3rd International Workshops on Turbulent Spray Combustion. The focus is on progress in experiments and numerical simulations for two-phase flows, with emphasis on spray combustion. Knowledge of the dominant phenomena and their interactions allows development of predictive models and their use in combustor and gas turbine design. Experts and young researchers present the state-of-the-art results, report on the latest developments and exchange ideas in the areas of experiments, modelling and simulation of reactive multiphase flows. The first chapter reflects on flame structure, auto-ignition and atomization with reference to well-characterized burners, to be implemented by modellers with relative ease. The second chapter presents an overview of first simulation results on target test cases, developed at the occasion of the 1st International Workshop on Turbulent Spray Combustion. In the third chapter, evaporation rate modelling aspects are covered, while the fourth chapter deals with evaporation effects in the context of flamelet models. In chapter five, LES simulation results are discussed for variable fuel and mass loading. The final chapter discusses PDF modelling of turbulent spray combustion. In short, the contributions in this book are highly valuable for the research community in this field, providing in-depth insight into some of the many aspects of dilute turbulent spray combustion.
Download or read book Droplets and Sprays written by Saptarshi Basu and published by Springer. This book was released on 2017-12-11 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on droplets and sprays relevant to combustion and propulsion applications. The book includes fundamental studies on the heating, evaporation and combustion of individual droplets and basic mechanisms of spray formation. The contents also extend to the latest analytical, numerical and experimental techniques for investigating the behavior of sprays in devices like combustion engines and gas turbines. In addition, the book explores several emerging areas like interactions between sprays and flames and the dynamic characteristics of spray combustion systems on the fundamental side, as well as the development of novel fuel injectors for specific devices on the application side. Given its breadth of coverage, the book will benefit researchers and professionals alike.
Download or read book Turbulent Combustion Modeling written by Tarek Echekki and published by Springer Science & Business Media. This book was released on 2010-12-25 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: Turbulent combustion sits at the interface of two important nonlinear, multiscale phenomena: chemistry and turbulence. Its study is extremely timely in view of the need to develop new combustion technologies in order to address challenges associated with climate change, energy source uncertainty, and air pollution. Despite the fact that modeling of turbulent combustion is a subject that has been researched for a number of years, its complexity implies that key issues are still eluding, and a theoretical description that is accurate enough to make turbulent combustion models rigorous and quantitative for industrial use is still lacking. In this book, prominent experts review most of the available approaches in modeling turbulent combustion, with particular focus on the exploding increase in computational resources that has allowed the simulation of increasingly detailed phenomena. The relevant algorithms are presented, the theoretical methods are explained, and various application examples are given. The book is intended for a relatively broad audience, including seasoned researchers and graduate students in engineering, applied mathematics and computational science, engine designers and computational fluid dynamics (CFD) practitioners, scientists at funding agencies, and anyone wishing to understand the state-of-the-art and the future directions of this scientifically challenging and practically important field.
Download or read book Modeling the Fuel Spray and Combustion Process of the Ignition Quality Tester with KIVA 3V written by and published by . This book was released on 2010 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: Developing advanced compression ignition and low-temperature combustion engines depends increasingly on chemical kinetic ignition models, but rigorous experimental validation of the models has been limited. Shock tubes and rapid compression machines are often limited to premixed gas-phase studies, precluding the use of realistic, low volatility diesel or biodiesel surrogates. The Ignition Quality Tester (IQT) constant-volume spray combustion system measures ignition delay of low-volatility fuels and could validate ignition models experimentally, but a better understanding of the IQT's processes is needed. KIVA-3V was used to develop a 3D CFD model that accurately reproduces ignition behavior and resolves temperature and equivalence ratio regions inside the IQT. The model's fuel spray characteristics (e.g., velocity) are experimentally validated, and it provides insight, vital to expanding the fuel research capabilities of the IQT, into the complex interaction between fuel spray and combustion processes.
Download or read book Fundamentals of Turbulent and Multiphase Combustion written by Kenneth Kuan-yun Kuo and published by John Wiley & Sons. This book was released on 2012-07-03 with total page 914 pages. Available in PDF, EPUB and Kindle. Book excerpt: Detailed coverage of advanced combustion topics from the author of Principles of combustion, Second Edition Turbulence, turbulent combustion, and multiphase reacting flows have become major research topics in recent decades due to their application across diverse fields, including energy, environment, propulsion, transportation, industrial safety, and nanotechnology. Most of the knowledge accumulated from this research has never been published in book form—until now. Fundamentals of Turbulent and Multiphase Combustion presents up-to-date, integrated coverage of the fundamentals of turbulence, combustion, and multiphase phenomena along with useful experimental techniques, including non-intrusive, laser-based measurement techniques, providing a firm background in both contemporary and classical approaches. Beginning with two full chapters on laminar premixed and non-premixed flames, this book takes a multiphase approach, beginning with more common topics and moving on to higher-level applications. In addition, Fundamentals of Turbulent and Multiphase Combustion: Addresses seven basic topical areas in combustion and multiphase flows, including laminar premixed and non-premixed flames, theory of turbulence, turbulent premixed and non-premixed flames, and multiphase flows Covers spray atomization and combustion, solid-propellant combustion, homogeneous propellants, nitramines, reacting boundary-layer flows, single energetic particle combustion, and granular bed combustion Provides experimental setups and results whenever appropriate Supported with a large number of examples and problems as well as a solutions manual, Fundamentals of Turbulent and Multiphase Combustion is an important resource for professional engineers and researchers as well as graduate students in mechanical, chemical, and aerospace engineering.
