PML Absorbing Boundary Condition for Nonlinear Euler Equations in Primitive Variables
نویسندگان
چکیده
Absorbing Boundary Condition for Nonlinear Euler Equations in primitive variables are presented based on the Perfectly Matched Layer (PML) technique. To facilitate the application of PML complex change of variables in the frequency domain, new auxiliary variables are introduced. The final form of the absorbing equations is presented in unsplit physical primitive variables. Both the two-dimensional Cartesian and axisymmetric cases are considered. Although the nonlinear absorbing equations are not theoretically perfectly matched, numerical experiments show satisfactory results. The derived equations are tested in numerical examples and compared with the PML absorbing boundary condition in conservation form that was formulated in an earlier work. No significant difference in performance is found for the two formulations. A comparison with the linear PML in nonlinear problems is also considered. It is found that using nonlinear PML significantly improves the performance of the absorbing boundary condition.
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