**5. Conclusions**

In this chapter, a LDR frequency excitation based vibro-thermography technique is implemented for detection of a circular delamination in a four layered GFRP plate. The analytical LDR frequency is calculated using the expression discussed in the theory section. The analytical LDR frequency is then confirmed by carrying out a steady state dynamic analysis. The mode shape obtained from the contour plot of the steady state analysis confirms the LDR frequency of the delamination which is further used for carrying out the explicit dynamic coupled temperature-displacement analysis. Subsequently, the amplitude-frequency spectra during the temperature-displacement analysis is plotted to observe a rise in temperature at the defect location due to clapping and rubbing action during resonance. The average nodal at delamination layer is presented to find the maximum temperature rise at delamination region when the plate is excited with LDR frequency. Moreover, a 10 ms heat transfer analysis is carried out to obtain high contrast temperature response on top surface of the GFRP plate. Finally, the temperature profile is plotted for all elements over the delamination layer after heat transfer
