Two-dimensional virtual array for ultrasonic nondestructive evaluation using a time-reversal chaotic cavity

J Acoust Soc Am. 2011 Nov;130(5):2720-7. doi: 10.1121/1.3643828.

Abstract

Despite its introduction more than a decade ago, a two-dimensional ultrasonic array remains a luxury in nondestructive evaluation because of the complexity and cost associated with its fabrication and operation. This paper describes the construction and performance of a two-dimensional virtual array that solves these problems. The virtual array consists of only two transducers (one each for transmit and receive) and an aluminum chaotic cavity, augmented by a 10 × 10 matrix array of rectangular rods. Each rod, serving as an elastic waveguide, is calibrated to emit a collimated pulsed sound beam centered at 2.5 MHz using the reciprocal time reversal. The resulting virtual array is capable of pulse-echo interrogation of a solid sample in direct contact along 10 × 10 scan lines. Three-dimensional imaging of an aluminum test piece, the nominal thickness of which is in the order of 1 cm, is successfully carried out using the virtual array.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aluminum
  • Equipment Design
  • Motion
  • Nonlinear Dynamics*
  • Signal Processing, Computer-Assisted*
  • Sound*
  • Time Factors
  • Transducers
  • Ultrasonics* / instrumentation

Substances

  • Aluminum