根据Pennes方程和毫米波在动物皮肤内的传播特性,建立了在33.5 GHz毫米波同辐照强度下的大鼠皮肤的非稳态多层传热模型.在二维柱坐标下进行离散计算,得到了长时间辐照条件下不同皮肤深度的温度变化规律,并将理论结果与实验数据进行了比较.在284 mW/cm2和853 mW/cm2辐照强度下,理论结果和实验结果基本一致；在474 mW/cm2和664 mW/cm2辐照强度下,有一定的误差,但误差仍不超过1℃,验证了该理论模型的准确性.分析了实际趋肤深度内的温度分布,发现毫米波引起的生物热效应的最高温度点并非在皮肤表面,而是皮下某点,其与表面辐照中心点的温差可超过1℃.进一步分析了血液灌注率对温度场的影响,发现在讨论的温度范围内,血液灌注率的变化对毫米波辐照下的皮肤表面温度场的影响较小.%We built up a transient thermal multilayer model for heating of human skin with high power millimeter waves by finite volume method (FVM) based on Pennes' bioheat transfer equation. We analyzed the calculated results and compared them with the experimental ones. The errors were no more than 1 ℃, especially at the incident power densities of 284 and 853 mW/cm2. The computing results agreed closely with the experimental ones. The veracity and reliability of finite volume model were validated. We charted the temperature changes with depth in the energy penetration depth at different radiation intensity of steady state. It was found that the maximum temperature spot caused by millimeter wave was not on the skin surface, but at some spot in subcutaneous. The difference in temperature between these two spots could be more than 1 ℃. The effect of blood perfusion rate on the temperature of skin surface was further analyzed. The change of blood perfu-sion rate had little effect on the temperature of skin surface in the temperature range studied in this paper.
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