Download or read book Atomization Modeling of Liquid Jets Using an Eulerian Eulerian Model and a Surface Density Approach written by Bejoy Mandumpala devassy and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In internal combustion engines, the liquid fuel injection is an essential step for the air/fuel mixture preparation and the combustion process. Indeed, the structure of the liquid jet coming out from the injector plays a key role in the proper mixing of the fuel with the gas in the combustion chamber. The present work focuses on the liquid jet atomization phenomena under Diesel engine conditions. Under these conditions, liquid jet morphology includes a separate liquid phase (i.e. a liquid core) and a dispersed liquid phase (i.e. a spray). This manuscript describes the development stages of a new atomization model, for a high speed liquid jet, based on an eulerian two-phase approach. The atomization phenomenon is modeled by defining different surface density equations, for the liquid core and the spray droplets. This new model has been coupled with a turbulent two-phase system of equations of Baer-Nunziato type. The process of ligament breakup and its subsequent breakup into droplets are handled with respect to available experiments and high fidelity numerical simulations. In the dense region of the liquid jet, the atomization is modeled as a dispersion process due to the turbulent stretching of the interface, from the side of liquid in addition to the gas side. Different academic test cases have been performed in order to verify the numerical implementation of the model in the IFP-C3D software. Finally, the model is validated with the recently published DNS results under typical conditions of direct injection Diesel engines.

Download or read book Development of a Next generation Spray and Atomization Model Using an Eulerian Lagrangian Methodology written by Wei Ning and published by . This book was released on 2007 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Modelling of Atomisation of Liquid Jets in Turbulent Flows written by Novid Beheshti and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Combined Eulerian Volume of Fraction Lagrangian Method for Atomization Simulation written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-13 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: The tracking of free surfaces between liquid and gas phases and analysis of the interfacial phenomena between the two during the atomization and breakup process of a liquid fuel jet is modeled. Numerical modeling of liquid-jet atomization requires the resolution of different conservation equations. Detailed formulation and validation are presented for the confined dam broken problem, the water surface problem, the single droplet problem, a jet breakup problem, and the liquid column instability problem. Seung, S. P. and Chen, C. P. and Ziebarth, John P. Unspecified Center...

Download or read book Spray and Atomization Characteristics of Liquid written by Hossam Said Mohamed Aly and published by Penerbit UTM Press. This book was released on with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues regarding spray and atomization of liquid that occur in many industrial applications are crucial for many combustion systems. However, a full understanding of such process is still lacking. In order to have a better understanding of the phenomena, numerical modeling of sprays would be a valuable tool in designing and assessing the performance of the combustion systems. Most multiphase computational fluid dynamics (CFD) models are classified into two categories: Eulerian–Lagrangian and Eulerian–Eulerian models. Although Eulerian–Lagrangian models are traditionally the most common choice for modeling spray problems, they include a large number of empirical sub–models and hence are very sensitive to fine tuning and rely heavily on the experiments. In this book, a newly developed mathematical model for calculating droplet break–up frequency based on both drag and turbulence induced fragmentation stresses is presented. The droplet break–up model was introduced into a CFD methodology based on the Eulerian–Eulerian approach, in which the mass and momentum conservation equations are solved for both phases. The CFD solver couples the population balance equation along with Navier–Stokes equations for tracking droplet diameters. The proposed mathematical model has the advantage of taking into account the effects of drag and turbulence stresses on the atomization process while abandoning the common disadvantages of current Lagrangian models. Numerical simulations were performed to model a coaxial air–blast atomizer using both the traditional Lagrangian model and the new Eulerian model.

Download or read book Direct and Large Eddy Simulation XII written by Manuel García-Villalba and published by Springer Nature. This book was released on 2020-05-09 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gathers the proceedings of the 12th instalment in the bi-annual Workshop series on Direct and Large Eddy Simulation (DLES), which began in 1994 and focuses on modern techniques used to simulate turbulent flows based on the partial or full resolution of the instantaneous turbulent flow structure. With the rapidly expanding capacities of modern computers, this approach has attracted more and more interest over the years and will undoubtedly be further enhanced and applied in the future. Hybrid modelling techniques based on a combination of LES and RANS approaches also fall into this category and are covered as well. The goal of the Workshop was to share the state of the art in DNS, LES and related techniques for the computation and modelling of turbulent and transitional flows. The respective papers highlight the latest advances in the prediction, understanding and control of turbulent flows in academic and industrial applications.

Download or read book Detailed Numerical Simulation of Liquid Jet in Crossflow Atomization with High Density Ratios written by Sina Ghods and published by . This book was released on 2013 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: The atomization of a liquid jet by a high speed cross-flowing gas has many applications such as gas turbines and augmentors. The mechanisms by which the liquid jet initially breaks up, however, are not well understood. Experimental studies suggest the dependence of spray properties on operating conditions and nozzle geometry. Detailed numerical simulations can offer better understanding of the underlying physical mechanisms that lead to the breakup of the injected liquid jet. In this work, detailed numerical simulation results of turbulent liquid jets injected into turbulent gaseous cross flows for different density ratios is presented. A finite volume, balanced force fractional step flow solver to solve the Navier-Stokes equations is employed and coupled to a Refined Level Set Grid method to follow the phase interface. To enable the simulation of atomization of high density ratio fluids, we ensure discrete consistency between the solution of the conservative momentum equation and the level set based continuity equation by employing the Consistent Rescaled Momentum Transport (CRMT) method. The impact of different inflow jet boundary conditions on different jet properties including jet penetration is analyzed and results are compared to those obtained experimentally by Brown & McDonell(2006). In addition, instability analysis is performed to find the most dominant insta- bility mechanism that causes the liquid jet to breakup. Linear instability analysis is achieved using linear theories for Rayleigh-Taylor and Kelvin- Helmholtz instabilities and non-linear analysis is performed using our flow solver with different inflow jet boundary conditions.

Download or read book Thermo and Fluid Dynamic Processes in Diesel Engines 2 written by James H. Whitelaw and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the second book edited with a selection of papers from the two-yearly THIESEL Conference on Thermo- and Fluid Dynamic Processes in Diesel Engines, organised by CMT-Mvtores Termicos of the Universidad Po/itecnica de Valencia, Spain. This volume includes versions of papers selected from those presented at the THIESEL 2002 Conference th held on lOth to 13 September 2002. We hope it will be the second volume of a long series reflecting the quality of the THIESEL Conference. This year, the papers are grouped in six main thematic areas: State of the Art and Prospective, Injection Systems and Spray Formation, Combustion and Emissions, Engine Modelling, Alternative Combustion Concepts and Experimental Techniques. The actual conference covered a wider scope of topics, including Air Management and Fuels for Diesel Engines and a couple of papers included reflect this variety. However, the selection of papers published here represents the most current preoccupations of Diesel engine designers, namely how to improve the combustion process using new injection strategies and alternative concepts such as the Homogeneous Charge Combustion Ignition.

Download or read book Handbook of Atomization and Sprays written by Nasser Ashgriz and published by Springer Science & Business Media. This book was released on 2011-02-18 with total page 922 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atomization and sprays are used in a wide range of industries: mechanical, chemical, aerospace, and civil engineering; material science and metallurgy; food; pharmaceutical, forestry, environmental protection; medicine; agriculture; meteorology and others. Some specific applications are spray combustion in furnaces, gas turbines and rockets, spray drying and cooling, air conditioning, powdered metallurgy, spray painting and coating, inhalation therapy, and many others. The Handbook of Atomization and Sprays will bring together the fundamental and applied material from all fields into one comprehensive source. Subject areas included in the reference are droplets, theoretical models and numerical simulations, phase Doppler particle analysis, applications, devices and more.

Download or read book New Results in Numerical and Experimental Fluid Mechanics VII written by Andreas Dillmann and published by Springer Science & Business Media. This book was released on 2010-10-05 with total page 629 pages. Available in PDF, EPUB and Kindle. Book excerpt: th This volume contains the papers presented at the 16 DGLR/STAB-Symposium held at the Eurogress Aachen and organized by RWTH Aachen University, Germany, November, 3 - 4, 2008. STAB is the German Aerospace Aerodynamics Association, founded towards the end of the 1970's, whereas DGLR is the German Society for Aeronautics and Astronautics (Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal Oberth e.V.). The mission of STAB is to foster development and acceptance of the discipline “Aerodynamics” in Germany. One of its general guidelines is to concentrate resources and know-how in the involved institutions and to avoid duplication in research work as much as possible. Nowadays, this is more necessary than ever. The experience made in the past makes it easier now, to obtain new knowledge for solving today's and tomorrow's problems. STAB unites German scientists and engineers from universities, research-establishments and industry doing research and project work in numerical and experimental fluid mechanics and aerodynamics for aerospace and other applications. This has always been the basis of numerous common research activities sponsored by different funding agencies. Since 1986 the symposium has taken place at different locations in Germany every two years. In between STAB workshops regularly take place at the DLR in Göttingen.

Download or read book Transport Phenomena In Combustion written by SH Chan and published by Taylor & Francis. This book was released on 2024-09-06 with total page 1862 pages. Available in PDF, EPUB and Kindle. Book excerpt: This two-volume set presents the proceedings from the 8th International Symposium on Transport Phenomena in Combustion. There are more than 150 chapters that provide an extensive review of topics such as complete numerical simulation of combustion and heat transfer in furnaces and boilers, the interaction of combustion and heat transfer in porous media for low emission, high efficiency applications, industrial combustion technology, experimental and diagnostic methods and active combustion control, and fire research, internal combustion engine, Nox and soot emission.

Download or read book Computational Methods in Multiphase Flow III written by Andrea Alberto Mammoli and published by WIT Press. This book was released on 2005 with total page 385 pages. Available in PDF, EPUB and Kindle. Book excerpt: A common feature of multiphase flows is that a dispersed or discontinuous phase is being carried by a continuous phase, for example water drops in gas flow, solid particles in water flow, or gas bubbles in liquid flow. The overall behavior of the flow is shaped largely by the interaction between the discontinuous elements--drops, particles, bubbles

Download or read book Modeling the Atomization of a Liquid Jet and Application of the Model to Large Diameter Molton Corium Jets written by Stuart Curtis Winquist and published by . This book was released on 1986 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book New Approaches for Modeling of Liquid Jet Atomization Processes written by and published by . This book was released on 1996 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes atomization simulations performed to investigate the role of this process in liquid rocket engine combustion instabilities. The research involves the development and application of a series of nonlinear free-surface models based on boundary element methods (BEMs). Models have been developed to study the effects of unsteady injection, transverse acoustic wave interactions (such as those experienced in the F-1 engine), longitudinal acoustic wave interactions, and the dynamics of droplets in the presence of an acoustic wave. Reults for each of these four models is presented in this document.

Download or read book Modeling Liquid Jet Atomization Processes written by and published by . This book was released on 1994 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report summarizes efforts in developing an analytic/numerical modeling capability for both steady and unsteady liquid jet atomization processes. The research involves the application of boundary element methods to model nonlinear deformation of liquid surfaces. An inviscid model has been developed to investigate dynamics of a finite-length jet which includes the presence of the orifice flow passages. In addition, a second model has been developed to simulate gas-phase interactions with the distorting jet surface. Preliminary developments associated with a viscous model are also discussed. (AN).

Download or read book Flow and Combustion in Reciprocating Engines written by C. Arcoumanis and published by Springer Science & Business Media. This book was released on 2009-06-29 with total page 427 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optimization of combustion processes in automotive engines is a key factor in reducing fuel consumption. This book, written by eminent university and industry researchers, investigates and describes flow and combustion processes in diesel and gasoline engines.

Download or read book OpenFOAM written by J. Miguel Nóbrega and published by Springer. This book was released on 2019-01-24 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains selected papers of the 11th OpenFOAM® Workshop that was held in Guimarães, Portugal, June 26 - 30, 2016. The 11th OpenFOAM® Workshop had more than 140 technical/scientific presentations and 30 courses, and was attended by circa 300 individuals, representing 180 institutions and 30 countries, from all continents. The OpenFOAM® Workshop provided a forum for researchers, industrial users, software developers, consultants and academics working with OpenFOAM® technology. The central part of the Workshop was the two-day conference, where presentations and posters on industrial applications and academic research were shown. OpenFOAM® (Open Source Field Operation and Manipulation) is a free, open source computational toolbox that has a larger user base across most areas of engineering and science, from both commercial and academic organizations. As a technology, OpenFOAM® provides an extensive range of features to solve anything from complex fluid flows involving chemical reactions, turbulence and heat transfer, to solid dynamics and electromagnetics, among several others. Additionally, the OpenFOAM technology offers complete freedom to customize and extend its functionalities.