Application of infinite-spectral hybrid method in 2.5-dimensional gravitational potential calculation

doi:10.7523/j.ucas.2022.041

Abstract

Abstract: Gravitational potential is an inseparable part of the earth’s free oscillation simulation. It is also the object of calculation in the study of gravity anomalies. Since the gravitational potential satisfies the unbounded Poisson-Laplace equation, which is zero at infinity, this is frustrating for numerical simulations. The purpose of numerical simulation is usually achieved by limiting the solution domain and approximating its boundary conditions. We attempt to use the infinite-spectral hybrid method to fit the infinity boundary directly and no longer approximate the boundary conditions. Considering the computational efficiency of the 3D Earth model, this study uses a 2.5-dimensional governing equation. Finally, numerical experiments verify the factual accuracy of this method.

Key words: infinite element, SEM, gravitational potential, 2.5D, Poisson-Laplace’s equation

CLC Number:

P312.1

REN Junsheng, ZHANG Huai. Application of infinite-spectral hybrid method in 2.5-dimensional gravitational potential calculation[J]. Journal of University of Chinese Academy of Sciences, 2024, 41(1): 65-69.

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