Tunable phononic crystal waveguides based on the double tuning method

To realize the frequency tuning of phononic crystals (PCs) and the functional design of tunable PCs, acoustic components with more flexible working frequencies are manufactured to meet the various requirements of engineering applications. We proposed a combined tuning method that combines the change of the Young’s modulus of the shape memory alloy and the rotation of the scatterer. The tunable band structure and transmission spectra of the method were calculated using the finite element method. We analyzed the effect of fill rate and viscosity of matrix on the band structure and studied the regulation law of the dual regulation mode. The numerical results show that the double tuning method makes up for the shortcomings of the single tuning method and has the characteristics of widely tuning range, continuous adjustment, and more tuning modes. In addition, a PC waveguide is constructed by using this combined tuning method, which realizes the flexible construction of waveguide channels and the continuous tuning of wide frequency range. It is an important guideline for the research of tunable waveguides, the design of acoustic components, and the application of practical engineering.