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Shock capturing by anisotropic diffusion oscillation reduction

G. W. Wei
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Abstract

This paper introduces the method of anisotropic diffusion oscillation reduction (ADOR) for shock wave computations. The connection is made between digital image processing,in particular, image edge detection, and numerical shock capturing. Indeed, numerical shock capturing can be formulated on the lines of iterative digital edge detection. Various anisotropic diffusion and super diffusion operators originated from image edge detection are proposed for the treatment of hyperbolic conservation laws and near-hyperbolic hydrodynamic equations of change. The similarity between anisotropic diffusion and artificial viscosity is discussed. Physical origins and mathematical properties of the artificial viscosity is analyzed from the kinetic theory point of view. A form of pressure tensor is derived from the first principles of the quantum mechanics. Quantum kinetic theory is utilized to arrive at macroscopic transport equations from the microscopic theory. Macroscopic symmetry is used to simplify pressure tensor expressions. The latter provides a basis for the design of artificial viscosity. The ADOR approach is validated by using (inviscid) Burgers' equation in one and two spatial dimensions, the incompressible Navier-Stokes equation and the Euler equation. A discrete singular convolution (DSC) algorithm is utilized for the spatial discretization.

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G. W. Wei. 2000-04-28. Shock capturing by anisotropic diffusion oscillation reduction. https://arxiv.org/abs/math/0004177

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