Thermal Relaxation Times in Biological Tissues Subjected to Pulsed Laser Irradiation
نویسندگان
چکیده
There are several expressions for calculating thermal relaxation time in tissues subjected to laser irradiation. Physically this time constant represents the time required for the temperature rise in a heated region of tissue to drop to a factor of e. In this study, we conduct combined radiation and heat conduction simulations to obtain this time constant for several different tissues, and compare the results with other mathematical expressions used for determining the thermal relaxation time. The scattering effect and surface convection are considered. A new thermal relaxation time expression is introduced in which its value is two times of the thermal relaxation time used in the literature. It is found that the results predicted by this new expression match better with the predictions based on the peak temperature decaying.
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