4. Conclusions

In this chapter, we used the transfer matrix method and Bloch theory to compute and study the propagation of mechanical waves through different 1D PnC structures with thermal effects. We performed numerical simulations to calculate the reflection coefficient and dispersion curves for the 1D PnC structure. We have discussed and studied the effects of many parameters on the phononic band gaps. The effects of temperature and defect mode on the properties of the PnC and on the localized modes were studied for both SH-waves and in-plane waves. The output results can be stated as follows:


devices that convert thermal energy into electricity. Hence after, the performance of many devices such as Peltier thermoelectric coolers, thermocouples, sensors, and thermoelectric energy generators can be enhanced. Moreover, the thermal conductivity of many structures could experience great changes based on the temperature gradients of PnCs. When temperature is increase in PnCs, the phononic band gap experiences a significant change.
