Weighted-averaging Finite-element Method for Scalar Wave Equation in the Frequency Domain

가중평균 유한요소법을 이용한 주파수영역에서의 인공 음향파 합성

  • 현혜자 (한국지질자원연구원 탐사개발연구부) ;
  • 서정희 (서울대학교 지구환경시스템공학부) ;
  • 민동주 (한국해양연구소 해양지질연구단)
  • Published : 2002.08.01

Abstract

We develop the weighted-averaging finite-element method which uses four kinds of element sets. By constructing global stiffness and mass matrices for four kinds of element sets and then averaging them with weighting coefficients, we obtain a new global stiffness and mass matrix. With the optimal weighting coefficients minimizing grid dispersion and grid anisotropy, we can reduce the number of grid points required per wavelength to 4 for a $1\%$ upper limit of error. We confirm the accuracy of our weighted-averaging finite-element method through accuracy analyses for a homogeneous and a horizontal-layer model. By synthetic data example, we reconfirm that our method is more efficient for simulating a geological model than previous finite-element methods.

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