The CEMRACS 2005 will be introduced by the Euromech Colloquium no. 467 on turbulent flow and noise generation from the 18th to the 20th of July.
Warning : If you want to attend the Euromech Colloquium, please register separately
here.
A survey of numerical methods for CAA.
Non-reflecting boundary condition is a critical component in developing Computational Aeroacoustics (CAA) algorithms. This presentation will review recent progresses on the application of the Perfectly Matched Layer (PML) technique to CAA problems.
An emerging theory of formulating PML absorbing boundary conditions for the governing equations of fluid dynamics will be discussed. This theory involves two essential steps.
First, a proper space-time transformation is determined and applied to the governing equations;
second, a PML complex change of variables is utilized for the derivation of time domain absorbing boundary conditions.
The proper space-time transformation ensures the stability of the boundary condition. Since the PML equation is perfectly matched (theoretically) to the physical governing equation, numerical reflections are generally very small which makes the PML technique attractive for CAA calculations.
Two- and three-dimensional examples of PML for the Euler equations will be given in this presentation. They include the solution of the linearized Euler equations with uniform and non-uniform mean flows as well as the absorption of convective vortices in the nonlinear Euler equations. Extensions of the PML to the viscous Navier-Stokes equations will also be discussed.
See abstract on the Euromech site.
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