Heat transfer mechanisms in thin film with laser heat source

The present study deals with the effect of laser radiation on the propagation phenomenon of a thermal wave in a very thin film subjected to a symmetrical heating on both sides. Pulsating laser heating is modelled as an internal heat source with various time characteristics. The Cattaneo heat flux law together with the energy conservation equation is solved by a numerical technique based on explicit scheme, i.e., MacCormack's predictor-corrector scheme. Results are obtained for the time history of heat transfer behaviour before and after symmetrical collision of wave fronts from two sides of a film. The study concludes (1) if the absorption coefficient of the continuously-operated- and pulsating-laser heat source increases, temperature overshoot causes in a very thin film within a very short period of time, and (2) the overshoot and oscillation of thermal wave depend on the frequency of the heat source time characteristics. This trend becomes minor in a thick film.