热传导方程的复杂性给研究激光热损伤等问题带来了困难,随机模拟算法将热传输看 成随机的化学动力学过程, 该算法容易实现,能适用于复杂系统随时间变化的模拟。基于随机模拟算法,模拟计算了光斑半径为5 μm, 波长为647 nm的高斯 激光辐照下硅表面层的二维热传输过程,探讨了硅反射系数、吸收系数、热容和热导率等热物 理参数随温度的变化对温度场分布的影响。结果表明,随机模拟算法的结果是合理的,在硅熔点范围内, 反射系数和热容可以取其平均值进行计算,有利于提高算法效率。

The complexity of the heat exchange equation brings difficulties to study laser-damage etc. A kind of stochastic method which treats the energy input and redistribution process as a chemical kinetics problem is used, and the thermal physical model is established. Based on stochastic method, the 2D distribution of temperature is studied by Gauss beam with 5 μm radius and 647 nm wavelength. The relationship of the temperature with irradiated time is obtained, and the effects on distribution of temperature are discussed about the variety of reflectance, absorption coefficient, thermal capacity and thermal conductance with temperature. The results indicate that stochastic method is reasonable to treat heat exchange, and the average of reflectance and thermal capacity can be used to improve simulating efficiency under the melting point of silicon.