Numerical analysis for micro-vibration isolation of jointed sandwich plates with mass blocks

The propagation property of micro-vibration wave and the energy distribution in the linear-shaped and L-shaped joint sandwich structures which contain mass blocks are investigated in this paper. The complex sandwich structure could be simplified according to the honeycomb panel equivalent theory. Then, the power transmission coefficients should be confirmed in different joint structures. Finally, the energy finite element method (EFEM) is developed to obtain the energy density of structures at the different frequencies by using the coefficients before. The results show that the sizes of mass block and the input frequencies of micro-vibration wave have important effects on isolation, and the bigger mass blocks have a better performance. From the results of energy distribution, the micro-vibration wave with low frequencies could be isolated effectively, but the isolation effect on micro-vibration with high frequencies is not obvious. In both of these structures, bending waves always exist, which also have important influence on the payload. However, longitudinal waves only exist in the L-shaped structures, and have a minor impact on them.