Coupled thermo-mechanical behavior of skin tissue irradiated by a pulse laser

The thermo-mechanical behavior within biological tissues irradiated by a pulse laser is studied in this paper. The governing equations involving the local heat non-equilibrium effect and thermo-mechanical coupled effect are proposed in the context of generalized thermo-elastic model with dual-phase-lag times. An effective procedure constructed on the finite difference method is then employed to solve these equations numerically. The values of phase-lag times rooted in the local heat non-equilibrium are estimated, and the interaction between the temperature and thermal deformation is also evaluated via an effective characteristic parameter. The thermo-mechanical response irradiated by a pulse laser as a therapeutic heat source has been predicted on this basis. The parametric study of the characteristic parameters including the effective phase-lag times and thermo-mechanical coupling factor on the temperature, displacement and stresses of the target tissue is further studied. The results state that the transport properties predicted by introduction of phase-lag times and their effect on tissue temperature, displacement and normal stresses are dominated by their ratio. Furthermore, the coupled effect between the temperature and thermal deformation can be evaluated by the thermo-mechanical coupled coefficient and can be ignored in the treatments on tissues with a small thermo-mechanical coefficient in general.