Structures with periodic features are widely utilized in the nature and also in the technical world. From an engineering point of view, the main interest of their characteristics is their simple manufacturing, significant impact and high temperature tolerance, and high strength-weight ratios. In addition, because of the vibration patterns of periodic structures, they provide manageable wave propagation characteristics which make them excellent candidates for the design of wave guides, frequency filters, or heat insulators. On the macro scale, examples of periodic structures include multi-span bridges, multi-blade turbines, chemical pipelines,stiffened plates and shells in aerospace and ship structures. On the other hand, any crystal (e.g. phononic crystals) can be thought of as a periodic structure in the micro scale order.The mathematical tool to investigate the wave propagation in these structures is mainly derived from Bloch theorem.
Design of modern transducers is shifting away from being a standalone technical premise and becoming more of an interdisciplinary area of study. This shift has been further expedited during recent years by introduction of the multiphysics simulation platforms. In the area of transducer design there are several unanswered research questions which are either purely theoretical or need minimal laboratory instruments. This include designing bone conduction transducers for wearable electronics and military applications and also vibration and acoustic sensors and actuators for health monitoring of manufacturing machines, bio compatible pumps and sensors.
On the other hand, in some other fields, while computer simulations are a necessary and obvious step for evaluating the design, computer simulations alone are often not considered to be sufficient for proof-of-concept. It is rather with performing validating tests under near-real-life working conditions that a proposed design or methodology can stand out as a viable solution.
Material Characterization Using Ultrasound
There are several research areas in this field. Recently, I have been working mainly on the issue of sensitivity in the resonant ultrasound spectroscopy (RUS). We strive to improve the accuracy of the result and enhance the sensitivity of the RUS.