Study of the low-frequency bandgap of ring-slotted spiral local resonant phononic crystal

In this paper, a ring-slotted spiral local resonant phononic crystal structure is investigated. The energy band characteristics and transmission losses of the structure are calculated using the finite element method. The numerical results show that the structure can generate bandgap in the range of 23.54–102.87 Hz. Combined with the modal coupling theory, the vibrational modes of the ring-slotted spiral local resonant phononic crystal are analyzed to reveal the bandgap formation mechanism of the structure. The effects of the various dimensional parameters and material hardness on the bandgap of the structure are analyzed by varying them. The results show that by varying the filling radius of silicone rubber in the ring-slotted spiral local resonant phononic crystal, the structure can be made to have an onset frequency of 19.42 Hz and generate a bandgap in the range of 19.42–78.16 Hz. A new idea is provided for the application of phononic crystal in low-frequency environment for vibration and noise reduction.