Abstract：Straight beam of locally resonant phononic crystals has apparent longitudinal vibration band gaps which are narrow with small attenuation and transverse vibration band gaps which are wide with strong attenuation generally. The two kinds of band gaps are often not in the same frequency band which makes it difficult to achieve multi-dimensional damping simultaneously. Aiming at this problem, in order to make fully use of the characteristics of strong attenuation and wide frequency band of transverse band gaps, a kind of locally resonant angle type beam of phononic crystals is proposed which can transform longitudinal wave into transverse wave. By using transfer matrix method on the theory analysis and numerical solution, and further simulation in finite element software . The results are compared with that of straight beam of phononic crystals showing that the vibrations on three degree of freedoms can be suppressed effectively in the same band. The structure of the angle type beam of phononic crystals is quite beneficial to meet the requirements of engineering multidimensional vibration damping and also expands the applications of phononic crystals.
2013, Vol. 32 
