Transient thermal analysis of layered media based on thermal quadrupoles

ABSTRACT The transient heat transfer within a layered structure can be modeled efficiently using the thermal quadrupole methods. Such numerical simulations would contribute to effective experimental design for thermography inspection applications of composite materials. Current research is part of such effort that focuses on the parametric study on both a two-layer model and a four-layer model. The variation of amplitude curves agrees with the lateral position of the interfacial discontinuity in general. The sudden increase in the phase value distinctively indicates the end point of the same discontinuity. Hence the lateral location of an embedded interfacial discontinuity can be readily identified from the Laplace surface temperature. The layer thickness does not have significant effect on the general trend observed in the parametric analysis presented in this work. The advantage of the numerical modeling of layered structures using thermal quadrupoles lies in that thermal quadrupoles can be easily extended to multiple layers containing internal anomaly between different layers.