Study on In-Plane Band Gap Characteristics of a Circular Periodic Structure Using DQM

A new two-dimensional periodic structure is proposed. This structure consists of curved beams with different radii of curvature and lengths spirally connected to each other to form a circle. Geometrical parameter effects on the first three in-plane vibration band gaps of this structure are studied using the differential quadrature method. Results show that for each set of the radii of curvature, as the lengths of inner beam elements increase, all the bands become close to each other. These close band gaps can be considerably enlarged by increasing the difference between the radii of curvature. Having close and wide band gaps means that this structure absorbs in-plane vibrations over a very wide frequency range. The dimensions of this structure are much smaller than other periodic structures due to its unique shape. All the mentioned features make this periodic structure an efficient vibration absorber. Validation of the analytical results is provided through the forced vibration analysis via ANSYS.