Effects of Aspect Ratio and Orientation Angle of Rectangular Inclusion on Self-Collimation Performance of Two-Dimensional Phononic Crystals

The present study proposes a method for improving the self-collimation performance of square array phononic crystals by means of orientated rectangular inclusions. Finite element simulations are performed to investigate the effects of the aspect ratio and orientation angle of rectangular inclusions on the self-collimation performance. The simulation results show that the proposed design provides an efficient self-collimation performance over both a high working frequency range and a wide incident angle range. Importantly, it is also shown that through an appropriate specification of the inclusion aspect ratio and orientation angle, both direction and degree of self-collimation beam and can be effectively manipulated. Overall, the present results show that the proposed design has significant potential for the realization of such applications as acoustic waveguides, collimators, and other phononic crystals-based systems.