Nonlinear to Linear Elastic Code Coupling in 2D Axisymmetric Media.
Abstract
Explosions within the earth nonlinearly deform the local media, but at typical seismological observation distances, the seismic waves can be considered linear. Although nonlinear algorithms can simulate explosions in the very near field well, these codes are computationally expensive and inaccurate at propagating these signals to great distances. A linearized wave propagation code, coupled to a nonlinear code, provides an efficient mechanism to both accurately simulate the explosion itself and to propagate these signals to distant receivers. To this end we have coupled Sandia's nonlinear simulation algorithm CTH to a linearized elastic wave propagation code for 2D axisymmetric media (axiElasti) by passing information from the nonlinear to the linear code via timevarying boundary conditions. In this report, we first develop the 2D axisymmetric elastic wave equations in cylindrical coordinates. Next we show how we design the timevarying boundary conditions passing information from CTH to axiElasti, and finally we demonstrate the coupling code via a simple study of the elastic radius.
 Authors:
 Sandia National Lab. (SNLNM), Albuquerque, NM (United States)
 Publication Date:
 Research Org.:
 Sandia National Lab. (SNLNM), Albuquerque, NM (United States)
 Sponsoring Org.:
 USDOE National Nuclear Security Administration (NNSA)
 OSTI Identifier:
 1376284
 Report Number(s):
 SAND20178848
656347
 DOE Contract Number:
 AC0494AL85000
 Resource Type:
 Technical Report
 Country of Publication:
 United States
 Language:
 English
 Subject:
 97 MATHEMATICS AND COMPUTING
Citation Formats
Preston, Leiph. Nonlinear to Linear Elastic Code Coupling in 2D Axisymmetric Media.. United States: N. p., 2017.
Web. doi:10.2172/1376284.
Preston, Leiph. Nonlinear to Linear Elastic Code Coupling in 2D Axisymmetric Media.. United States. doi:10.2172/1376284.
Preston, Leiph. 2017.
"Nonlinear to Linear Elastic Code Coupling in 2D Axisymmetric Media.". United States.
doi:10.2172/1376284. https://www.osti.gov/servlets/purl/1376284.
@article{osti_1376284,
title = {Nonlinear to Linear Elastic Code Coupling in 2D Axisymmetric Media.},
author = {Preston, Leiph},
abstractNote = {Explosions within the earth nonlinearly deform the local media, but at typical seismological observation distances, the seismic waves can be considered linear. Although nonlinear algorithms can simulate explosions in the very near field well, these codes are computationally expensive and inaccurate at propagating these signals to great distances. A linearized wave propagation code, coupled to a nonlinear code, provides an efficient mechanism to both accurately simulate the explosion itself and to propagate these signals to distant receivers. To this end we have coupled Sandia's nonlinear simulation algorithm CTH to a linearized elastic wave propagation code for 2D axisymmetric media (axiElasti) by passing information from the nonlinear to the linear code via timevarying boundary conditions. In this report, we first develop the 2D axisymmetric elastic wave equations in cylindrical coordinates. Next we show how we design the timevarying boundary conditions passing information from CTH to axiElasti, and finally we demonstrate the coupling code via a simple study of the elastic radius.},
doi = {10.2172/1376284},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 8
}

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