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Showing 1 to 16 of 16 for “"Riemann Solver"”.
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Adjoint sensitivity analysis of the two-phase two-fluid model based on an approximate Riemann solver
A new shock-capturing upwind numerical solver (i.e. forward solver) and an adjoint sensitivity analysis framework for the two-phase two-fluid model are developed and verified. Both the numerical solver and the adjoint sensitivity analysis framework are based on an analytical analysis of the …
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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
… bed topography and wetting-drying fronts. A Riemann-solver finite volume scheme, using primitive variables rather than conserved variables, and a semi-discrete Streamline Upwind Petrov-Galerkin (SUPG) method in finite element context are applied to compare the performance of these two …
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The unstructured grid incompressible Navier-Stokes algorithm for convective heat transfer based on artificial compressibility
… in a time marching fashion. Roe's approximate Riemann solver is used for the construction of the numerical flux. An eigensystem is derived for the flux Jacobian matrix, which is used in the evaluation of the numerical flux and the characteristic variable boundary conditions. The resulting …
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A Volume of Fluid (VoF) based all-mach HLLC Solver for Multi-Phase Compressible Flow with Surface-Tension
… Lax, Leer and Contact (HLLC) approximate Riemann solver based on Garrick et al. [1] is developed and combined with the popular Volume of Fluid (VoF) method: Compressive Interface Capturing Scheme for Arbitrary Meshes (CICSAM). This novel combination yields a scheme with both HLLC shock …
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Discontinuous Galerkin Based Multi-Domain Multi-Solver Technique for Efficient Multiscale Electromagnetic Modeling
… multiscale problems. With the help of the Riemann solver (upwind flux), a discontinuous Galerkin based multi-domain multi-solver technique is introduced in this work for multiscale electromagnetic modeling. Specifically, the proposed technique allows multiple subdomains and multiple …
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Accelerating The Discontinuous Galerkin Cell-Vertex Scheme (Dg-Cvs) Solver On Cpu-Gpu Heterogeneous Systems
… is an efficient, accurate and robust numerical solver for general hyperbolic conservation laws. It can solve a broad range of conservation laws such as the shallow water equation and Magnetohydrodynamics equations. Dg-Cvs is a Riemann-Solver-free high order space-time method for arbitrary space …
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Kinetic algorithms for non-equilibrium gas dynamics
… show that even though the KFVS scheme is a Riemann solver at the kinetic level, its behavior at the Euler level is more similar to the the existing flux-vector splitting algorithms than to the flux-difference splitting scheme of Roe. A new approach toward the development of a genuinely …
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The numerical study of 3-dimensional laminar hypersonic blunt-fin interactions
… order Godunov method with a HLLC approximate Riemann solver; second order accuracy is achieved through the MUSCL approach. The viscous contribution is modeled by a centered difference scheme. An iterative matrix solver is used to advance the implicit solution in time. To handle large …
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Efficient finite-volume schemes for magnetohydrodynamic simulations in solar physics
… dimensions. We introduce a new approximate Riemann solver for the ideal gas MHD equations (MHD-HLLEM) that outperforms all other solvers considered. We present and compare several Riemann solvers that are suitable for the real gas case of an arbitrary equation of state (EOS) (e.g., RGDW and …
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On the simulation and modeling for the reaction mechanism and solid state detonation phenomena in non-conventional explosives
… of numerical methods, including approximate Riemann solver, splitting method, higher-order interpolation and vacuum tracking method combined with the general equations of state. Our scheme can used for calculating TOA (Time of Arrival) of particles to the sensors in TOFMS and for …
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Two-dimensional Euler computations on a triangular mesh using an upwind, finite-volume scheme
… are developed for implementing Roe's approximate Riemann solver on unstructured grids. Higher order accuracy is achieved by using MUSCL-differencing. MUSCL-differencing is implemented on an unstructured grid by interpolating the values stored at the vertices of triangular elements to find the …
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Nonlinear Acoustic Waves Generated by Surface Disturbances and Their Effect on Lower Thermospheric Composition
… method of is implemented in Clawpack with a Riemann Solver to solve the Euler Equations including multiple species, defined by their mass fractions, as they undergo advection. Viscous dissipation and thermal conduction are applied via a fractional step method. The model is validated with …
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Preconditioning methods for ideal and multiphase fluid flows
… multiphase multispecies compressible fluid flow solver using homogeneous equilibrium mixture model. The mathematical model for fluid flow going through phase change uses density and temperature in the formulation, where the density represents the multiphase mixture density. The change of phase of …
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Near-wall similarity in three-dimensional turbulent boundary layers
… upwind schemes utilizing Roe’s approximate Riemann solver are developed. For the cell-vertex scheme, a four stage Runge-Kutta time integration with and without implicit residual averaging, a point Jacobi method, a symmetric point Gauss-Seidel method, and two methods utilizing preconditioned …
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The development of solution algorithms for compressible flows
… upwind schemes utilizing Roe’s approximate Riemann solver are developed. For the cell-vertex scheme, a four stage Runge-Kutta time integration with and without implicit residual averaging, a point Jacobi method, a symmetric point Gauss-Seidel method, and two methods utilizing preconditioned …
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Adaptive Discontinuous Galerkin Methods Applied to Multiscale & Multiphysics Problems towards Large-scale Modeling & Joint Imaging
… improvements. Especially, I will show innovative Riemann solvers, inspired by physical meanings, in a unified mathematical framework, which are the key to guaranteeing the stability and accuracy of the DG methods and domain decomposition methods.</p>