The implementation and validation of a phased array probe model into the simSUNDT software

Paper in proceeding, 2014

Ultrasonic phased array technique has gone from being a unique technique with few and very specific purposes into being an established tool and replacing conventional contact technique in a broad field of applications. Even though the far-field behaviour is more or less identical to single crystal techniques the knowledge in e.g. how it differentiates in interaction with defects and geometry closer to the probe is rather limited. A thorough validated mathematical model based on the physics has the ability to overcome this lack of understanding and is the only realistic alternative in the development of new procedures based on this technique. The simSUNDT software consists of a Windows®-based preprocessor and postprocessor together with a mathematical kernel (UTDefect), dealing with the actual mathematical modelling. The model employs various integral transforms and integral equation and enables simulations of the entire ultrasonic testing situation. In the latest released version (2.0) a model of phased array probe has been incorporated. Each of its elements is in the model represented by the boundary conditions that generate a plane wave, at a certain angle, in the far field. These boundary conditions (i.e. the pressure on the surface under the element) are then translated into the main coordinate system and after superposition they built up a phased array wave front (constructive phase interference) with prescribed nominal angle. Modelling has been identified as an effective tool and in a previous work the developed methodology based on simulations of a well defined procedure was validated. In this paper a new model of phased array technique is implemented in the simSUNDT software and thoroughly validated.