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Showing 1 to 19 of 19 for “"finite-volumen"”.
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Numerische Simulation nichtlinearer Aeroakustik bei kleinen Machzahlen
… zur Zeitdiskretisierung, als auch die Güte der Finite-Volumen-Diskretisierung auf unstrukturierten Gittern werden hinsichtlich ihrer Dispersions- und Dämpfungsfehler verglichen. Zusätzlich werden nichtreflektierende Randbedingungen in die implizite Diskretisierung eingebettet, damit störende …
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Diskretisierungsverfahren für Systeme von Konvektions-Diffusions-Dispersions-Reaktions-Gleichungen und Anwendungen
… man die explizite Zeitdiskretisierung und die finite Volumen-Methode für die Raumdiskretisierung. Dabei splittet man die mehr-dimensionalen Konvektions-Reaktions-Gleichungen in ein-dimensionale Probleme und verwendet die Godunovs-Methode. Für den Transport-Schritt wird dabei die analytische …
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Entwicklung eines effizienten Verfahrens zur Simulation kompressibler Strömungen in 3D auf Parallelrechnern
… der Betrachtungen ist ein explizites Finite Volumen Verfahren zur Simulation kompressibler zeitabhängiger dreidimensionaler Überschallströmungen zusammen mit einem unstrukturierten Hexaedernetz, das durch eine lokale Gitterweitenanpassung die Verteilung der Freiheitsgrade entsprechend …
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Solving the system of Radiation Magnetohydrodynamics : for solar physical simulations in 3d
In this study we present a finite-volumen scheme for solving the equations of radiation magnetohydrodynamics in two and three space dimensions. Among other applications this system is used to model the plasma in the solar convection zone and in the solar photosphere. It is a non--linear system of …
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Unstructured h-adaptive finite volume schemes for compressible viscous fluid flow
… The spatial discretization is based on a finite volume scheme for two- and three-dimensional flow problems. Thereby, the grid is considered as a fully unstructured mesh, composed of simply connected elements with otherwise arbitrary topology. The method is of second order accuracy in space …
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Finite volume schemes for hyperbolic-parabolic systems : error estimates
Finite-volume schemes on unstructured grids are the most frequently used <br>to approximate solutions of systems of hyperbolic balance laws in multi-space dimension. <br>The convergence analysis for the scalar case is well developed, even though <br>not complete up to now. In contrast, very few is …
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Probability Density Function Modeling of Turbulent Non-reactive and Reactive Spray Flows
… Modell geschlossen. Es wird durch eine hybride Finite-Volumen/Lagrange Monte-Carlo Methode gelöst. Ein turbulentes, nicht reagierenden Sprays wird damit simuliert. Die numerischen Resultate der PDF Methode sind in guter Übereinstimmung mit den experimentellen Daten aus der Literatur und …
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Numerical modeling of incompressible flow applied to casting processes
… chain. The simulation program CASTS is based on finite element (FE) approximations. Recently a hybrid approach was developed combining the mathematics of finite elements with the technical advantages of the finite volume (FV) method. In this work a flow solver for the hybrid FE/FV method has been …
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Parametric multi-block grid generation and application to adaptive flow simulations
… that usually underlies the philosophy of finite element or finite volume methods. This is especially true for adaptive codes. Here, for instance, one faces the problem that once a standard polygonal grid has been constructed, subsequent grid refinement requires information from the exact …
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High-order well-balanced finite volume schemes for geophysical flows : development and numerical comparisons
… In the second part we compare a classical finite-difference and a high order finite-volume scheme for barotropic ocean flows. We compare the schemes with respect to their accuracy, stability, and study various outflow and inflow boundary conditions. We apply the schemes to the problem of …
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Computergestützte Analyse des reaktiven Strömungsmischens in T-Mikroreaktoren
… residence time and the reaction time. Using the finite volume method the full resolution of all length scales is obtained by a combination of simulations on a 3-D and a 2-D grid: the transport equations for mass, momentum and species concentration are solved on a 3D grid as long as the flow of …
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Three-dimensional staggered grids for systems of hyperbolic conservation laws
… an impressively simple Riemann-solver free Finite Volume staggered grid scheme for the approximate solution of systems of conservation laws in one spatial dimension. The scheme itself is a natural extension of the first order Lax-Friedrichs scheme to second order accuracy. The better …
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Micromechanical material models for polymer composites through advanced numerical simulation techniques
… on the methodology of building up an appropriate finite element material model describing the microstructure of the composite. It contains numerical homogenization practice and theory, as well as micro structural material modeling by using numerical simulation techniques on representative volume …
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Adaptive timestepping for conservation laws via adjoint error representation
… of the dual solution and its projection to the finite element space. We can show that it is therefore sufficient to compute the spatial gradient of the dual solution. This gradient satisfies a conservation law instead of a transport equation, and it can therefore be computed with the same …
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Iterative solvers in implicit time integration for compressible flows
… key issue is the development of a new adaptive finite volume flow solver called QUADFLOW. Therein, certain iterative methods that arise in most CFD simulations are used for the simulation of compressible flow around an airfoil. QUADFLOW is designed for the stationary and non-stationary …
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Multidimensional modeling of the thermal and flow regime in the western part of the Molasse Basin, Southern Germany
… groundwater modeling codes are based on the finite differences or finite volume method for orthogonal grids. In cases of complex subsurface geometries this type of grid either leads to coarse geometric representations or to extremely fine meshes. Therefore, a coordinate transformation method …