Nonlocal behavior in thermal lagging

Abstract

Nonlocal behavior during thermal lagging is studied in this work to accommodate the effect of the thermomass (TM) of the dielectric lattices. Perfect correlations are established, with the lagging time in the TM model equivalent to the phase lag of the heat flux vector and the length parameter in the TM model equivalent to the correlating length describing the nonlocal response. Simultaneous existence of the nonlocal (in space) and lagging (in time) behaviors give rise to a new type of thermal waves, which can be many times faster than the Cattaneo–Vernotte waves. Nonlinear behaviors of the phase lag and the correlating length are considered in the general model to study their influences on suppressing the sharp wavefronts. Dominating parameters are extracted to characterize the nonlocal response with thermal lagging.