Share Email Print
cover

Proceedings Paper

Poroelastic model for acoustic land mine detection
Author(s): Y. Zeng; Qing Huo Liu
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Acoustic waves can be a viable tool for the detection and identification of land mines and unexploded ordnance. Design of acoustic instruments and interpretation and processing of acoustic measurements call for accurate numerical models to simulate acoustic wave propagation in a heterogeneous soil with buried objects. Compared with the traditional seismic exploration, high attenuation is unfortunately ubiquitous for shallow surface acoustic measurements because of the loose soil and the fluid in its pore space. To adequately model such acoustic attention, we propose a comprehensive model to simulate the acoustic wave interactions with land mines and soils based on the Biot theory for poroelastic media. The finite-difference time-domain method is then used to solve the Biot equations. For the truncation of the computational domain in the FDTD method, we extend the acoustic and elastic perfectly matched layer (PML) to poroelastic media. Numerical experiments show that, with only 10 cells of PML medium, a high attenuation of about 50 dB can be achieved for outgoing waves. The numerical model is validated by comparison with analytical solutions. Unlike the pure elastic wave mode, this efficient PML-FDTD model for poroelastic media incorporates the interactions of waves and the fluid-saturated variation with offset in three different ground media: dry sand, fully water saturated sand and partly water saturated sand. The interaction of elastic wave with a plastic mine buried in dry sand ins simulated. The results show that the surface wave is significantly influenced by the existence of a mine-like object. The diffraction of the surface wave can serve as an acoustic target signature.

Paper Details

Date Published: 22 August 2000
PDF: 12 pages
Proc. SPIE 4038, Detection and Remediation Technologies for Mines and Minelike Targets V, (22 August 2000); doi: 10.1117/12.396304
Show Author Affiliations
Y. Zeng, Duke Univ. (United States)
Qing Huo Liu, Duke Univ. (United States)


Published in SPIE Proceedings Vol. 4038:
Detection and Remediation Technologies for Mines and Minelike Targets V
Abinash C. Dubey; James F. Harvey; J. Thomas Broach; Regina E. Dugan, Editor(s)

© SPIE. Terms of Use
Back to Top