A coupled time-space model is established in a polar coordinate to obtain the propagation characters from some monopole sources distributed evenly on a rigid cylinder. Following the least-squares variational principle
Chebyshev spectral element method is chosen to discretize both the time and space domains and the problem in polar coordinate is transformed into cylindrical coordinate. The validity of this model is verified by the numerical experiment
and the acoustic wave propagation on a rigid cylinder with C-E-M absorbing boundary condition on the edge of computational domain is revealed. The results show that a high-order accuracy can be obtained by the coupled time-space model via matching the numerical accuracy between time and space. The numerical accuracy can be improved by increasing the number of the elements or the interpolation order in each element of time and space. An exponential accuracy rate can be obtained with the increasing interpolation order. The acoustic wave propagation on the surface of a rigid cylinder can be simulated stably by this model
and the C-E-M absorbing boundary condition rewritten as the Dirichlet boundary condition still works well.
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references
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