Modeling Ultrasounds for Nondestructive Testing Applications

The ultrasonic techniques are today one of the most used methods for nondestructive testing (NDT) and for the characterization of the materials. Often it is necessary to simulate the system under test before to apply this technique to the real case. In fact, during the test in general a great number of parameters have to be calibrated in order to maximize the information captured by means of the measurements. In this chapter we will give some examples of ultrasonic NDT applications. The first one is a tutorial example and it considers the simulation of ultrasonic waves within a fish tank. The next two examples are concerned with the application of ultrasonic testing to masonry and concrete structures, respectively. In particular the problems of detecting a void in a trachite stone wall and in a concrete pillar are considered. Finally, the last example presented here is concerned with the detection of a hole in a metallic specimen. In fact, the ultrasonic inspection technique is widely employed in the steel industry due to favorable propagation conditions that such materials ensure. All the simulations have been done using COMSOL as finite element analysis, solver, and simulation software.