Open Access Open Access  Restricted Access Subscription or Fee Access

Development of a Generalized Excitation Algorithm for Modeling Phased Array Acoustic Sensors Using Distributed Point Source Method



Phased array ultrasonic technology has seen significant development for the last decade. Phased array sensors allow faster electronic scanning compared to an equivalent conventional sensor. It also facilitates the steering the probe without physically moving the sensor. In recent years researchers are using phased transducers to develop improved and efficient ultrasonic inspection techniques, but little emphasis were given on developing new modeling techniques which could lead to the development of a more sophisticated and precise sensors. In this paper, a new approach of modeling phased array sensors using Distributed Point Source Method (DPSM) has been described. DPSM is a mesh free semi analytical technique that has been developed for solving a variety of engineering problems such as ultrasonic, magnetic, and electrostatic. The sensor surface is discretized into an array of half spheres and theoretical point sources are placed at the center of those spheres. The total acoustic field is calculated by summing up the contribution of each individual point source. For a phased array sensor, the angle and the strength of the acoustic beam depend on the number, placement and activation frequency of the point sources. In this paper, an excitation algorithm for the point sources has been developed. The algorithm is developed to accommodate any arbitrary shape of the transducer face to generate strong focused acoustic beams. The algorithm also optimizes the density function and placement location of point sources on the transducer face. In this research, it has been shown that optimized technique can be successfully applied for modeling micro scale phased array sensors

doi: 10.12783/SHM2015/378

Full Text: