By multiple-scattering theory (MST), disorder effect on the focus image in steel/water phononic crystal panel with negative refraction was investigated. It was found that sonic waves within certain frequency range can propagate along certain directions in periodic crystal and form a focus image with negative refraction characteristics. These directional pathways depend on the periodic scattering in the crystal and are different from the ordinary positional guide. Obstacles in pathways have a deep influence on the focus image. With the increasing of degrec of positional disorder of cylinders, the periodic scattering decreases, pathways are broken, and the focus image becomes blurred or disappears.
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