Experimental verification of the acoustic computer model using triangle reflector

Abstract

Objective of this study was experimental verification of the acoustic computer model, which enables calculation of the signals reflected by triangles arbitrally oriented in space. Verification of the computer model was carried out comparing the C-scan images of triangle reflectors, obtained experimentally and by simulation in the case when ultrasonic beam is reflected by triangle reflectors, reflecting surfaces of which are perpendicular and inclined with respect to the symmetry axis of the directivity pattern.
Comparison of the experimental and simulated results of the inclined triangle reflector revealed some discrepancies. In order to find out the reason of these discrepancies the assumption was made that during rotation of the triangle reflector, the rotation axis was not strictly perpendicular to the incident ultrasonic beam, but that it was slightly deflected. In order to check this hypothesis modelling was also performed at different transducer deflection angles from its supposed position for each triangle angle. The simulation results clearly show that this assumption was correct and correspondence between experimental and simulation results in this case (0.75° deflection) is obtained much better.