Impedance boundary conditions for a time-domain finite-point method

  • Carlos Spa
  • Ricardo Rivas
  • Luis Pérez
Technical Paper


In this paper, we present the formulation of a time-domain impedance boundary model based on a finite-point approximation. Firstly, the scalar wave equation is numerically treated studying either the stability or the dispersion error in the case of a Cartesian regular mesh with standard clouds and weighted functions. Then, we develop the formulation of a locally reacting impedance boundary model suitable for the whole acoustic impedance range, and we carried out several numerical experiments to confirm the accuracy and the performance of the full model. Lastly, some conclusions and remarks of the method are discussed.


Finite-point method Impedance boundary conditions Time-domain simulations 



The work of the authors is partially funded by Projects FONDECYT 11140212 (Chile), Advanced Center for Electrical and Electronic Engineering (AC3E) Basal Project FB0008 (Chile) and the European Unions Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 644602.

Compliance with ethical standards

Conflicts of interest

The author(s) declare(s) that there is no conflict of interest regarding the publication of this paper.


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Copyright information

© The Brazilian Society of Mechanical Sciences and Engineering 2018

Authors and Affiliations

  1. 1.Department of MathematicsUniversidad Técnica Federico Santa MaríaValparaisoChile
  2. 2.Department of Mechanical EngineeringUniversidad Técnica Federico Santa MaríaValparaisoChile

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