Diversion of energy flow near crack tips of a vibrating plate using the structural intensity technique

The structural intensity (SI) of a vibrating rectangular plate with a crack is computed using the finite element method. The overall behavior of power flow patterns of the cracked plate is investigated. The presence of the crack can be identified by the changes of the directions of SI vectors near the crack. The effects of orientation of the crack and crack length on the energy flow pattern are also investigated. The SI method is then used to explore the positioning of dampers in vibrating thin plates to divert the vibration energy flow away from crack tips. This approach is proposed as a temporary measure to prevent further propagation of the crack before repair of the crack can be done.