基于DPL模型对超短脉冲激光辐照金属薄板传热行为的渐进分析

Asymptotic analysis of heat transfer behavior of metal sheet irradiated by ultra-short pulse laser based on DPL model

基于双相滞后热传导模型(DPL模型),对超短脉冲激光辐照金属薄板的瞬态热传导行为进行了渐进分析.首先在一维条件下基于双相滞后热传导模型联合能量守恒方程得出金属薄板的热传导偏微分控制方程,然后利用Laplace正、逆变换的技术和近似求解的方法,推导了金属薄板在超短脉冲激光热冲击下的温度变化的近似解析表达式.将结果与文献中数值方法结果进行了比较,验证了解析方法的准确性.研究了热通量相位滞后值和温度梯度的相位滞后值以及金属薄板板厚对热传递行为的影响.结果表明:随着热通量的相位滞后值的增加,超短脉冲激光加热引起的热波的波峰值越高,温度变化率越大;相反,随着温度梯度的相位滞后值的增加,该热波的波峰值越低,温度变化率减小;此外,金属薄板板厚对相对温度变化的波形影响较小.

Based on the dual phase lag heat conduction model(DPL model),the asymptotic analysis of the transient heat conduction behavior of a thin metal sheet irradiated by ultra-short pulse laser was conducted.The governing equation with temperature representation of a thin metal plate was proposed in the context of the DPL model.The asymptotic solutions of temperature distribution through the whole thin plate induced by external ultra-short pulse laser were derived by combing the Laplace transform and the inverse transform techniques.The results were compared with those from the numerical methods in the literature to verify the accuracy of the analytical method.The effects of the phase-lag termsτq,τT and the sheet metal thickness on heat transfer behavior were also investigated.The results show that the peak value of heat wave and the change rate of temperature are increased with the increasing ofτq.On the contrary,as theτT increases,the peak value of heat wave and the temperature change rate are decreased.The metal plate thickness has slight effect on the temperature change.