Fourier Galerkin Approach to Wave Equation with Absorbing Boundary Conditions

Numerical computation of wave propagation in a large
domain usually requires significant computational effort. Hence, the
considered domain must be truncated to a smaller domain of interest.
In addition, special boundary conditions, which absorb the outward
travelling waves, need to be implemented in order to describe the
system domains correctly. In this work, the linear one dimensional
wave equation is approximated by utilizing the Fourier Galerkin
approach. Furthermore, the artificial boundaries are realized with
absorbing boundary conditions. Within this work, a systematic work
flow for setting up the wave problem, including the absorbing
boundary conditions, is proposed. As a result, a convenient modal
system description with an effective absorbing boundary formulation
is established. Moreover, the truncated model shows high accuracy
compared to the global domain.

Authors:

• Alexandra Leukauf
• Alexander Schirrer
• Emir Talic

Keywords:

• Absorbing boundary conditions
• boundary control
• Fourier Galerkin approach
• modal approach
• wave equation.

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