Development of an experimental arrangement for precise measurement of angular distribution of ultrasound scattering

Abstract

This paper describes step-by-step development of a custom-made measurement system and also provides an assessment of the reliability of the set-up. The angular distribution of the scattered field generated by a sufficiently long cylindrical scatterer in water medium has been measured by this system. The measured values have been compared with the theoretical results to validate the instrument. The theoretical curves have been obtained by using the Faran’s theory [<i style="">J Acoust Society of</i> <i style="">America</i>, 23(4) (1951) 405]. In this study, an acoustic wave of frequency 2.19 MHz emitted by a medical ultrasound source has been employed to provide energy to the scattering object. Two steel wires of different gauges (0.68mm and 0.91mm in diameter) with size parameters k<i style=""><img src='/image/spc_char/alpha.gif' border=0> </i> ≈ 3.12 and 4.17, respectively, have been taken as prototype scatterers. Here, k is the wave number of the incident wave and <i style=""><img src='/image/spc_char/alpha.gif' border=0> </i> is the radius of the target. Our results show that the system is stable, capable of precise scattering measurements and measured values are reproducible. The system has also the flexibility of incorporating scatters of different shapes and also ultrasound probes of different frequencies.