SCHMERR L W1 HUANG R1 SEDOV A2

(1 Center for NDE, Iowa State University Ames, Iowa, USA )

(2 Department of Mechanical Engineering, Lakehead University Thunder Bay, ON, Canada)

Received Oct. 27 , 2009

Revised Jan. 11, 2010

Abstract Point Sources and Gaussian Beams are used frequently as fundamental building blocks for developing ultrasonic beam models. Both these models have different weaknesses that limit their effectiveness. Here, we will show that one can develop a Gaussian Beam Equivalent Point Source (GBEPS) model that removes those weaknesses and combines the accuracy and versatility of the point source models with much of the speed and well-behaved nature of Gaussian beam models. We will demonstrate the efficiency and versatility of this new GBEPS model in simulating the beams generated form ultrasonic phased arrays, using as few as one Gaussian beam per element of the array. A signal element GBEPS model will be shown to be as accurate as a point source model even when substantial beam focusing or steering is present in the array or where the array beam is transmitted through an interface. At the same time the GBEPS model will be shown to be several orders of magnitude faster than the point source model.

PACS numbers: 43.20, 43.35