Download or read book A Multiple Level Set Approach for Modeling Unconstrained Solidification written by Hasan Shetabivash and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis focuses on numerical simulation of the freezing process of liquid droplets on cold substrates. Solidification of droplets is one of the most challenging phenomenon for numerical modelling since various complicated physical mechanisms are involved. Dealing with the jump conditions at interfaces has been a long-term concern in numerical simulations. Moreover, the tri-junction point where three-phases come into contact requires special treatment. Furthermore, density expansion during freezing process should be taken into account. In this thesis, we propose a level-set based model to represent three-phase solidification physics. Liquid and solid interfaces are represented by two different level-sets in order to deal with the phases separately. The liquid-gas interface is advected under an external velocity field obtained from solving Navier-Stokes equations. The solid-liquid level-set, on the other hand, evolves according to the freezing rate of the liquid. The level-set associated with the solid-liquid interface is comprised of two segments: active, and passive. The active part of the level-set evolves based on temperature gradients and latent heat of fusion. While, the passive part is merely utilized for imposing the angle at the tri-junction point. We solve a Hamilton-Jacobi type equation in the passive part of the liquid-solid interface to impose a constant or variable angle at the tri-junction point. Furthermore, to consider the effect of density expansion, we added a source term into the continuity equation. The source term induces velocity in the domain by which the liquid-gas interface evolves. Moreover, a source term is added to the level-set advection equation to impose mass conservation in the liquid phase. The effect of density variation is included in the energy equation as well. The proposed numerical approach is validated using benchmark problems. In addition, we compared numerical results of water droplet freezing on a cold substrate with experimental results available in the literature. Through the comparison, we prove that the proposed model is capable of accurately predicting solidification behavior.
Download or read book Quantitative Phase Field Modelling of Solidification written by Nikolas Provatas and published by CRC Press. This book was released on 2021-10-12 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a study of phase field modelling of solidification in metal alloy systems. It is divided in two main themes. The first half discusses several classes of quantitative multi-order parameter phase field models for multi-component alloy solidification. These are derived in grand potential ensemble, thus tracking solidification in alloys through the evolution of the chemical potentials of solute species rather than the more commonly used solute concentrations. The use of matched asymptotic analysis for making phase field models quantitative is also discussed at length, and derived in detail in order to make this somewhat abstract topic accessible to students. The second half of the book studies the application of phase field modelling to rapid solidification where solute trapping and interface undercooling follow highly non-equilibrium conditions. In this limit, matched asymptotic analysis is used to map phase field evolution equations onto the continuous growth model, which is generally accepted as a sharp-interface description of solidification at rapid solidification rates. This book will be of interest to graduate students and researchers in materials science and materials engineering. Key Features Presents a clear path to develop quantitative multi-phase and multi-component phase field models for solidification and other phase transformation kinetics Derives and discusses the quantitative nature of the model formulations through matched interface asymptotic analysis Explores a framework for quantitative treatment of rapid solidification to control solute trapping and solute drag dynamics
Download or read book Multiscale Modeling of Solidification of Multi component Alloys written by Lijian Tan and published by . This book was released on 2007 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: Modeling solidification in the micro-scale is computationally intensive. To overcome this difficulty, a method combining features of front-tracking methods and fixed-domain methods is developed. To explicitly track the interface growth and shape of the solidifying crystals, a front-tracking approach based on the level set method is implemented. To easily model the heat and momentum transport, a fixed-domain method is implemented assuming a diffused freezing front where the liquid fraction is defined in terms of the level set function. The fixed-domain approach, by avoiding the explicit application of essential boundary conditions on the freezing front, leads to an energy conserving methodology that is not sensitive to the mesh size. Techniques including fast marching, narrow band computing and adaptive meshing are utilized to speed up computations. The model is used to investigate various phenomena in solidification including two- and three-dimensional dendrite growth of pure material and alloys, eutectic and peritectic solidification, convection effects on crystal and dendrite growth, planar/cellular/dendritic transition, interaction between multiple dendrites, columnar/equiaxed transition and etc. Interaction between thousands or even millions of crystals gives the overall behavior of the solidification process and defines the properties of the final product. A multiscale model based on a database approach is developed to investigate alloy solidification. Appropriate assumptions are introduced to describe the behavior of macroscopic temperature, macroscopic concentration, liquid volume fraction and microstructure features. These assumptions lead to a macroscale model with two unknown functions: liquid vol- ume fraction and microstructure features. These functions are computed using information from microscale solutions of selected problems. A computationally efficient model, which is different from the microscale and macroscale models, is utilized to find relevant sample problems. The microscale solution of the relevant sample problems is then utilized to evaluate the two unknown functions (liquid volume fraction and microstructure features) in the macroscale model. The temperature solution of the macroscale model is further used to improve the estimation of the liquid volume fraction and microstructure features. Interpolation is utilized in the feature space to greatly reduce the number of required sample problems. The efficiency of the proposed multiscale framework is demonstrated with numerical examples that consider a large number of crystals. A computationally intensive fully-resolved microscale analysis is also performed to evaluate the accuracy of the multiscale framework. (Abstract).
Download or read book Solid Liquid Thermal Energy Storage written by Moghtada Mobedi and published by CRC Press. This book was released on 2022-06-22 with total page 361 pages. Available in PDF, EPUB and Kindle. Book excerpt: Solid–Liquid Thermal Energy Storage: Modeling and Applications provides a comprehensive overview of solid–liquid phase change thermal storage. Chapters are written by specialists from both academia and industry. Using recent studies on the improvement, modeling, and new applications of these systems, the book discusses innovative solutions for any potential drawbacks. This book: Discusses experimental studies in the field of solid–liquid phase change thermal storage Reviews recent research on phase change materials Covers various innovative applications of phase change materials (PCM) on the use of sustainable and renewable energy sources Presents recent developments on the theoretical modeling of these systems Explains advanced methods for enhancement of heat transfer in PCM This book is a reference for engineers and industry professionals involved in the use of renewable energy systems, energy storage, heating systems for buildings, sustainability design, etc. It can also benefit graduate students taking courses in heat transfer, energy engineering, advanced materials, and heating systems.
Download or read book Comprehensive Materials Processing written by and published by Newnes. This book was released on 2014-04-07 with total page 5485 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive Materials Processing, Thirteen Volume Set provides students and professionals with a one-stop resource consolidating and enhancing the literature of the materials processing and manufacturing universe. It provides authoritative analysis of all processes, technologies, and techniques for converting industrial materials from a raw state into finished parts or products. Assisting scientists and engineers in the selection, design, and use of materials, whether in the lab or in industry, it matches the adaptive complexity of emergent materials and processing technologies. Extensive traditional article-level academic discussion of core theories and applications is supplemented by applied case studies and advanced multimedia features. Coverage encompasses the general categories of solidification, powder, deposition, and deformation processing, and includes discussion on plant and tool design, analysis and characterization of processing techniques, high-temperatures studies, and the influence of process scale on component characteristics and behavior. Authored and reviewed by world-class academic and industrial specialists in each subject field Practical tools such as integrated case studies, user-defined process schemata, and multimedia modeling and functionality Maximizes research efficiency by collating the most important and established information in one place with integrated applets linking to relevant outside sources
Download or read book Annual Index abstracts of SAE Technical Papers written by and published by . This book was released on 2006 with total page 1000 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Level Set Methods and Dynamic Implicit Surfaces written by Stanley Osher and published by Springer Science & Business Media. This book was released on 2006-04-06 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Very hot area with a wide range of applications; Gives complete numerical analysis and recipes, which will enable readers to quickly apply the techniques to real problems; Includes two new techniques pioneered by Osher and Fedkiw; Osher and Fedkiw are internationally well-known researchers in this area
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1992 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2005 with total page 884 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Multilevel Theory Research and Methods in Organizations written by Katherine J. Klein and published by Pfeiffer. This book was released on 2000 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study on multilevel analysis cuts through the confusion surrounding the development and testing of multilevel theories. It illuminates processes and effects within organisations, synthesising and updating current theory.
Download or read book Numerical Algorithms written by Justin Solomon and published by CRC Press. This book was released on 2015-06-24 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical Algorithms: Methods for Computer Vision, Machine Learning, and Graphics presents a new approach to numerical analysis for modern computer scientists. Using examples from a broad base of computational tasks, including data processing, computational photography, and animation, the textbook introduces numerical modeling and algorithmic desig
Download or read book Continuum Scale Simulation of Engineering Materials written by Dierk Raabe and published by John Wiley & Sons. This book was released on 2006-03-06 with total page 885 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book fills a gap by presenting our current knowledge and understanding of continuum-based concepts behind computational methods used for microstructure and process simulation of engineering materials above the atomic scale. The volume provides an excellent overview on the different methods, comparing the different methods in terms of their respective particular weaknesses and advantages. This trains readers to identify appropriate approaches to the new challenges that emerge every day in this exciting domain. Divided into three main parts, the first is a basic overview covering fundamental key methods in the field of continuum scale materials simulation. The second one then goes on to look at applications of these methods to the prediction of microstructures, dealing with explicit simulation examples, while the third part discusses example applications in the field of process simulation. By presenting a spectrum of different computational approaches to materials, the book aims to initiate the development of corresponding virtual laboratories in the industry in which these methods are exploited. As such, it addresses graduates and undergraduates, lecturers, materials scientists and engineers, physicists, biologists, chemists, mathematicians, and mechanical engineers.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1992 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Simulation Methods for Polymers written by Michael Kotelyanskii and published by CRC Press. This book was released on 2004-03-01 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Unified Constitutive Equations for Creep and Plasticity written by A.K. Miller and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: Constitutive equations refer to 'the equations that constitute the material response' at any point within an object. They are one of the ingredients necessary to predict the deformation and fracture response of solid bodies (among other ingredients such as the equations of equilibrium and compatibility and mathematical descriptions of the configuration and loading history). These ingredients are generally combined together in complicated computer programs, such as finite element analyses, which serve to both codify the pertinent knowledge and to provide convenient tools for making predictions of peak stresses, plastic strain ranges, crack growth rates, and other quantities of interest. Such predictions fall largely into two classes: structural analysis and manufacturing analysis. In the first category, the usual purpose is life prediction, for assessment of safety, reliability, durability, and/or operational strategies. Some high-technology systems limited by mechanical behavior, and therefore requiring accurate life assess ments, include rocket engines (the space-shuttle main engine being a prominent example), piping and pressure vessels in nuclear and non-nuclear power plants (for example, heat exchanger tubes in solar central receivers and reformer tubes in high-temperature gas-cooled reactors used for process heat applications), and the ubiquitous example of the jet engine turbine blade. In structural analysis, one is sometimes concerned with predicting distortion per se, but more often, one is concerned with predicting fracture; in these cases the informa tion about deformation is an intermediate result en route to the final goal of a life prediction.
Download or read book Publications of the National Institute of Standards and Technology Catalog written by National Institute of Standards and Technology (U.S.) and published by . This book was released on 1990 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Introduction to Computational Science written by Angela B. Shiflet and published by Princeton University Press. This book was released on 2014-03-30 with total page 857 pages. Available in PDF, EPUB and Kindle. Book excerpt: The essential introduction to computational science—now fully updated and expanded Computational science is an exciting new field at the intersection of the sciences, computer science, and mathematics because much scientific investigation now involves computing as well as theory and experiment. This textbook provides students with a versatile and accessible introduction to the subject. It assumes only a background in high school algebra, enables instructors to follow tailored pathways through the material, and is the only textbook of its kind designed specifically for an introductory course in the computational science and engineering curriculum. While the text itself is generic, an accompanying website offers tutorials and files in a variety of software packages. This fully updated and expanded edition features two new chapters on agent-based simulations and modeling with matrices, ten new project modules, and an additional module on diffusion. Besides increased treatment of high-performance computing and its applications, the book also includes additional quick review questions with answers, exercises, and individual and team projects. The only introductory textbook of its kind—now fully updated and expanded Features two new chapters on agent-based simulations and modeling with matrices Increased coverage of high-performance computing and its applications Includes additional modules, review questions, exercises, and projects An online instructor's manual with exercise answers, selected project solutions, and a test bank and solutions (available only to professors) An online illustration package is available to professors
