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In this study, classical and generalized dual phase lag bioheat transfer models are applied for investigate thermal damage to skin tissue exposed to the transient heat flux. The analytical bioheat transfer analysis with transient heat flux on skin tissue has only been studied by Pennes and thermal wave models. This paper, for the first time, provides the analytical solution of the dual phase lag model in skin tissue under transient surface heating using Laplace transform method and inversion theorem. Since the dual phase lag model under certain circumstances reduces to the Pennes and thermal wave models, comparisons of the temperature responses and thermal damages between the these three models are carried out. The influence of porosity factor and coupling factor between blood and tissue on the thermal damage of tissue is investigated and the results demonstrate that increases in these factors respectively leads to the higher and lower tissue thermal damage and the effects of these factors on the thermal damage in the depth of tissue is lower than near the surface.

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New surgical technologies are continuously being developed to enhance control during operations and mitigate injuries resulting from surgical procedures. One such advancement is the ultrasonic laparoscopic surgical tool known as the ultrasonic scalpel, which is designed to minimize surgery-related injuries when used alongside conventional tools. Establishing optimal input parameters for this ultrasonic instrument not only enhances operational reliability but also decreases the risk of resultant injuries. Ongoing research investigates the impact of varying power and duration of ultrasonic vibrations, along with the equivalent energy input into the blood vessel during surgery, on tissue mechanical characteristics and thermal effects. This study assesses the ability of sheep carotid artery tissues to withstand blood pressure within the vessel and examines thermal damage through pressure testing and optical imaging. Findings indicate that maintaining constant time at specific power yields maximum pressure tolerance at optimal power levels. However, varying the time at specific power settings produces different effects. For instance, the highest blood pressure resistance, at 1100 mmHg, was observed at 44 Watt of power over a 10 second duration at 10 newton. Furthermore, results demonstrate that increased energy input correlates with heightened thermal damage to surrounding tissues during the operation.