Aiming at the problem of low-frequency vibration and noise reduction in the engineering field, a new two-dimensional tapered scatterer phononic crystals slab is designed and the bandgap characteristics and displacement vector field of the model are simulated by means of finite element method. The numerical simulations show that an extremely wide complete bandgap can be achieved at low frequency. Compared with the reference model [Acoust. Phys. 65 (2019) 322], the first complete bandgap of the designed model has a lower starting frequency and a wider bandgap which is expanded by nearly 15 times. Moreover, the mechanism of bandgap generation is analyzed, the influences of geometric parameters and structure symmetry on the band structure are also investigated.
