In the present work, the thermal effects of a CW laser on skin tissues with blood perfusion are simulated. For this purpose, a one-dimensional medium is considered that is exposed to the laser beams from one side and the other side is at the constant temperature (37℃) because of being touched by other parts of the body. The laser beams are considered to be collimated and perpendicular to the surface of the tissue. The skin tissue is a strong anisotropic scattering medium and is assumed to be gray with black walls. Also, the blood perfusion is considered in the bioheat transfer equation of the skin tissue. The governing equations of this problem are radiative heat transfer coupled with conductive heat transfer that the discrete ordinates method, finite volume method and scaling method is used to solve the radiative transfer equation, the energy equation and to model the anisotropic scattering of the tissue, respectively. Validation of the model is performed by comparison with the other related works. Then, the effects of different optical and physical parameters of tissue such as conduction-radiation parameter, scattering albedo, extinction coefficient, blood perfusion and the effects of laser power on the time of temperature increase of the tissue and thermal penetration depth are studied. It should be mentioned that the results of the present study show valuable guidance for understanding the coupled light and bioheat transport in tissues in therapy, surgery and diagnostic tasks.

Keywords: CW laser, Living Tissue, Blood Perfusion, Radiation-Conduction, Discrete Ordinates Method (DOM)

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