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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 17 of 17 for “"Moving boundary problems"”.
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New results in stochastic moving boundary problems
Moving boundary problems arise in many areas of science and engineering and they are of great importance in the areas of partial differential equations (PDEs) since they characterize phase change phenomena where a system has two phases such as solid and liquid. However, unlike other PDEs in a …
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A sharp interface isogeometric strategy for moving boundary problems
… any point on the interface, allowing for complex boundary conditions dependent on curvature or normal to be naturally imposed. Thus, the enriched approximation naturally captures the interfacial discontinuity in temperature gradient and enables the imposition of Gibbs-Thomson condition during …
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Algebraic level sets for CAD/CAE integration and moving boundary problems
<p>Boundary representation (B-rep) of CAD models obtained from solid modeling kernels are commonly used in design, and analysis applications outside the CAD systems. Boolean operations between interacting B-rep CAD models as well as analysis of such multi-body systems are fundamental operations on …
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A Study of the Volume of Fluid Method for Moving Boundary Problems
<p>Moving boundary problems are often encountered in engineering and science. One of the methods to solve such problems numerically is the volume of fluid (VOF) method. The VOF method uses an additional field variable/to track the interface using the Eulerian fixed grid. In this work, the VOF …
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Arbitrary Lagrangian-Eulerian form of flowfield dependent variation (ALE-ADV) method for moving boundary problems
… was originally developed to solve complex flow problems through the use of so-called implicitness parameters. These parameters determine the implicitness of FDV method by evaluating local gradients of physical flow parameters, hence vary across the computational domain. The method has been used …
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Método dos elementos de contorno aplicado a propagação de ondas gravitacionais não lineares
This work presents a boundary element method formulation in two-dimensions, to be applied either to moving boundary problems, or to problems with non moving boundaries. Isoparametric quadratic elements have been implemented to discretize the boudary. The procedure developed for non moving boundary …
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Convective mass transport for viscous flow past an evolving boundary
"A Boundary Integral-Spectral Element method is developed that solves two-dimensional Helmholtz equations. This high order technique is shown to be adaptable to a variety of boundary conditions and solves elliptic partial differential equations efficiently such that it is applicable to moving …
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Topics in geometric analysis with applications to partial differential equations
… the mathematical tools and methods used to study problems which bridge between analysis and geometry. Such an undertaking is particularly useful in situations in which the geometry is variable, such as: -- the theory of minimal surfaces, in differential geometry -- shape analysis and …
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DEVELOPMENT OF GAS KINETIC FLUX SOLVERS AND THEIR APPLICATIONS
… developed and applied to solve a variety of flow problems. Firstly, two types of GKFSs have been successfully proposed for both inviscid and viscous flow simulations. The developed solvers have been validated in a variety of 1D to 3D flow simulations. Numerical results demonstrate that the present …
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Phase-field Modeling of Phase Change Phenomena
… method has become a popular numerical tool for moving boundary problems in recent years. In this method, the interface is intrinsically diffuse and stores a mixing energy that is equivalent to surface tension. The major advantage of this method is its energy formulation which makes it easy to …
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Development of an Immersed Boundary Method for the Simulation of Moving Bodies at Fluid-fluid Interfaces
… This thesis presents the development of Immersed Boundary Methods (IBMs) coupled to a two-phase incompressible flow solver. The phases are treated as immiscible, and are modelled using the Volume-of-Fluid (VOF) method. The methods developed to include the effects of surface tension and contact …
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Automatic higher order mesh generation and movement utilizing spring-field and vector-adding
… an advancing-layer method to avoid mesh quality problems in transition areas, while using spring models to complement the advancing-layers by smoothing the mesh, especially in medial axis regions. After generating the linear mesh, a higher-order finite-element ready, curved mesh is obtained by …
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Solution of fully-coupled shallow water equations and contaminant transport using a primitive variable Riemann solver and a semi-discrete SUPG method
… applied to compare their performance for wet-bed problems and a shock-capturing scheme is implemented to accommodate shock wave fronts. Linear triangular elements are used to decompose the computational domain and a second-order backward differentiation (BDF2) implicit method is used for the time …
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Numerical Modeling of Polyvinyl Alcohol (PVA) Swelling and Dissolution in Water
… models from literature. In solving the double moving boundary problems of swelling and dissolution, Landau transform is introduced to deal with the changing domains. An iterative scheme to track the location of the moving boundary demarking the polymer-solvent intersection at every time step …
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Simulations of diffusion driven phase evolution in heterogenous solids
… in solids include crack propagation, grain boundary motion, diffusion driven void motion through sur- face and bulk diffusion. The presence and evolution of these over the life-cycle of electronics components such as metal lines and solder joints presents a significant reliability challenge. …
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The Diffuse Bounce Back Lattice Boltzmann Method and its Applications on the Study of Fluid-Particle Interactions
… and parallel algorithm. Both sharp and diffuse boundary treatments are studied to recover curved and moving boundaries on structured orthogonal grids for the lattice Boltzmann method. These methods can describe curved boundaries more accurately and more smoothly than the naive staircase …
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Κίνηση, παραμόρφωση και αλληλεπίδραση φυσαλίδων λόγω βαρύτητας ή/και μεταβολής της πίεσης του περιβάλλοντος ρευστού
Αντικείμενο της παρούσας εργασίας είναι η πρόβλεψη τόσο της κίνησης, αλληλεπίδρασης και παραμόρφωσης δύο φυσαλίδων λόγω μεταβολής της πίεσης στο περιβάλλον ιξώδες υγρό, όσο και της ανοδικής κίνησης μιας φυσαλίδας λόγω άνωσης σε ένα Νευτωνικό ή ιξωδοπλαστικό ρευστό. Για τη μοντελοποίηση των …