Download or read book Numerical Simulation of Dendritic Solidification with Convection written by Nabeel Zahran Al-Rawahi and published by . This book was released on 2002 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Simulation of Dendritic Solidification Using a Phase Field Model written by and published by . This book was released on 1996 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Simulation of Dendritic Solidification Using a Phase Field Model written by and published by . This book was released on 2000 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Simulation of Dendritic Solidification written by Huizi Hao and published by . This book was released on 1993 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling Dendritic Solidification Using Lattice Boltzmann and Cellular Automaton Methods written by Mohsen Eshraghi and published by . This book was released on 2013 with total page 103 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation presents the development of numerical models based on lattice Boltzmann (LB) and cellular automaton (CA) methods for solving phase change and microstructural evolution problems. First, a new variation of the LB method is discussed for solving the heat conduction problem with phase change. In contrast to previous explicit algorithms, the latent heat source term is treated implicitly in the energy equation, avoiding iteration steps and improving the formulation stability and efficiency. The results showed that the model can deal with phase change problems more accurately and efficiently than explicit LB models. Furthermore, a new numerical technique is introduced for simulating dendrite growth in three dimensions. The LB method is used to calculate the transport phenomena and the CA is employed to capture the solid/liquid interface. It is assumed that the dendritic growth is driven by the difference between the local actual and local equilibrium composition of the liquid in the interface. The evolution of a threedimensional (3D) dendrite is discussed. In addition, the effect of undercooling and degree of anisotropy on the kinetics of dendrite growth is studied. Moreover, effect of melt convection on dendritic solidification is investigated using 3D simulations. It is shown that convection can change the kinetics of growth by affecting the solute distribution around the dendrite. The growth features of twodimensional (2D) and 3D dendrites are compared. Furthermore, the change in growth kinetics and morphology of Al-Cu dendrites is studied by altering melt undercooling, alloy composition and inlet flow velocity. The local-type nature of LB and CA methods enables efficient scaling of the model in petaflops supercomputers, allowing the simulation of large domains in 3D. The model capabilities with large scale simulations of dendritic solidification are discussed and the parallel performance of the algorithm is assessed. Excellent strong scaling up to thousands of computing cores is obtained across the nodes of a computer cluster, along with near-perfect weak scaling. Considering the advantages offered by the presented model, it can be used as a new tool for simulating 3D dendritic solidification under convection.
Download or read book Numerical Simulation of Solidification written by Jin-Young Jung and published by . This book was released on 2000 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Interactive Dynamics of Convection and Solidification written by S.H. Davis and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: The phase transformation from liquid to solid is a phenomenon central to a wide range of manufacturing and natural processes. The presence of phase transformation can drive convection in the melt through the liberation of latent heat, the rejection of solute, and the change of density upon freezing. The fluid mechanics itself can playa central role; the phase transformation can be strongly altered by convective transport in the liquid through the modification of the thermal and solutal environment of the solid-liquid interface; these local fields control the freezing characteristics at the interface. The convection can be generated naturally by buoyancy forces arising from gradients of temperature and concentration in the liquid, by density changes upon freezing, and by thermocapillary and solutocapillary forces on liquid-solid interfaces. The interactive coupling between solidification and convection forms the subject of this volume. Such coupled processes are significant on a large range of scales. Among the applications of interest are the manufacture of single crystals, the processing of surfaces using laser or molecular beams, and the processes of soldering and welding. One wants to understand and predict macrosegregation in castings, transport and fractionation in geological and geophysical systems, and heat accumulation in energy redistribution and storage systems. This volume contains papers presented at the NATO Advanced Research Workshop on "Interactive Dynamics of Convection and Solidification" held in Chamonix, France, March 8-13, 1992.
Download or read book A Fixed grid Numerical Method for Dendritic Solidification with Natural Convection written by Patrick M. Lahey and published by . This book was released on 1999 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transient Numerical Simulation of Complex Convection Effects During Solidification in Casting and Welding written by Georg Ehlen and published by . This book was released on 2004 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Interactive Dynamics of Convection and Solidification written by Peter Ehrhard and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crystal growth, casting, soldering, welding, high-energy surface treatment, nuclear safety systems and geophysical flows are just a few examples where solidification and convection occur together. These processes are interactive on micro- and macroscales: flow affects the distribution of heat and species and hence the freezing process, while solidification evolves flow boundaries, as in crusting, for example, and hence can radically alter the convection. Mathematical modellers, experimentalists and applied scientists were invited to this colloquium with the aim of consolidating our understanding of such interactions, of identifying key outstanding issues, and of developing new approaches in this important area of fundamental research. Both invited and contributed papers focus on both fundamental and technologically relevant problems.
Download or read book Thermosolutal Convection and Macrosegregation in Dendritic Alloys written by National Aeronautics and Space Adm Nasa and published by . This book was released on 2018-11 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: A mathematical model of solidification, that simulates the formation of channel segregates or freckles, is presented. The model simulates the entire solidification process, starting with the initial melt to the solidified cast, and the resulting segregation is predicted. Emphasis is given to the initial transient, when the dendritic zone begins to develop and the conditions for the possible nucleation of channels are established. The mechanisms that lead to the creation and eventual growth or termination of channels are explained in detail and illustrated by several numerical examples. A finite element model is used for the simulations. It uses a single system of equations to deal with the all-liquid region, the dendritic region, and the all-solid region. The dendritic region is treated as an anisotropic porous medium. The algorithm uses the bilinear isoparametric element, with a penalty function approximation and a Petrov-Galerkin formulation. The major task was to develop the solidification model. In addition, other tasks that were performed in conjunction with the modeling of dendritic solidification are briefly described. Poirier, David R. and Heinrich, J. C. Unspecified Center...
Download or read book Phase field Simulation of Dendritic Growth Under Externally Applied Deformation written by Masashi Yamaguchi and published by . This book was released on 2011 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: Defects, i.e. hot tears, macrosegragation, and pores, formed in metal castings are a result of stresses and strains in the solid-liquid mushy zone. Numerical simulation of solidification of deforming dendrite crystal promises to improve insight into the mechanical behavior of mushy zones under an applied load. The primary goal of this thesis is to develop numerical methodologies for performing solidification simulation of deforming dendrites. Such simulation encounters difficulties associated with the interface dynamics due to phase change or interaction among the dendrites, and large visco-plastic deformation applied to them. Phase-field simulation of dendritic solidification is promising for the treatment of the complex interface dynamics. Free energy based formulation allows the model to incorporate bridging and wetting phenomena occurring at grain boundaries through an extra energy term which arises from a mismatch of the crystallographic orientation. The particle method would be attractive to handle large inelastic deformation without suffering mesh entanglement. In order to investigate the effect of solid deformations on the evolving microstructure, the material point method with elasto-visco-plasticity constitutive model is developed to couple to a phase-field model of solidification. The changes in the crystallographic orientation of a growing dendrite crystal due to solid deformation are carefully accounted for through the coupling methodology. The developed numerical framework is applicable to the simulation for single and multiple crystals, and is capable of handling complex morphological change. The wide variety of validations and practical problems solved in this thesis demonstrates the capability of investigating deformation behavior of growing crystals.
Download or read book CFD Modeling and Simulation in Materials Processing 2016 written by Laurentiu Nastac and published by Springer. This book was released on 2017-08-31 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Multiscale Modelling of the Influence of Convection on Dendrite Formation and Freckle Initiation During Vacuum Arc Remelting written by Lang Yuan and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lattice Boltzmann Modeling written by Michael C. Sukop and published by Springer Science & Business Media. This book was released on 2007-04-05 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here is a basic introduction to Lattice Boltzmann models that emphasizes intuition and simplistic conceptualization of processes, while avoiding the complex mathematics that underlies LB models. The model is viewed from a particle perspective where collisions, streaming, and particle-particle/particle-surface interactions constitute the entire conceptual framework. Beginners and those whose interest is in model application over detailed mathematics will find this a powerful 'quick start' guide. Example simulations, exercises, and computer codes are included.
Download or read book Solidification written by Michel Rappaz and published by EPFL Press. This book was released on 2009-08-21 with total page 656 pages. Available in PDF, EPUB and Kindle. Book excerpt: Solidification is one of the oldest processes for producing useful implements and remains one of the most important modern commercial processes. This text describes the fundamentals of the technology in a coherent way, using consistent notation.
Download or read book Computational Thermo Fluid Dynamics written by Petr A. Nikrityuk and published by John Wiley & Sons. This book was released on 2011-09-19 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: Combining previously unconnected computational methods, this monograph discusses the latest basic schemes and algorithms for the solution of fluid, heat and mass transfer problems coupled with electrodynamics. It presents the necessary mathematical background of computational thermo-fluid dynamics, the numerical implementation and the application to real-world problems. Particular emphasis is placed throughout on the use of electromagnetic fields to control the heat, mass and fluid flows in melts and on phase change phenomena during the solidification of pure materials and binary alloys. However, the book provides much more than formalisms and algorithms; it also stresses the importance of good, feasible and workable models to understand complex systems, and develops these in detail. Bringing computational fluid dynamics, thermodynamics and electrodynamics together, this is a useful source for materials scientists, PhD students, solid state physicists, process engineers and mechanical engineers, as well as lecturers in mechanical engineering.
