激光线源作用于铝管产生温度场梯度的有限元分析

Analysis of the Temperature Gradient Fields Induced by a Line-source Laser in Hollow Aluminum Cylinders Using Finite Element Method

用有限元方法数值分析了激光线源作用于铝管时产生的温度场梯度,给出了不同时刻切向和法向温度梯度等值线分布。数值结果表明:材料内部温度分布极不均匀,产生很大的温度梯度;切向温度梯度沿径向在样品的表面区域达到最大,沿周向在激光强度的空间分布变化最明显的位置值最大;法向温度梯度的最大值点沿径向随时间推移逐渐向材料内部移,沿周向在激光线源中心处最大。

The transient temperature gradient fields generated by a line-source laser in aluminum pipe are calculated by using the finite element method. The isoline distributions of the tangential and normal temperature gradient are obtained at various time. The numerical results denoted： the great temperature gradient exists quite unevenly inside the material. In radial orientation, the tangential temperature gradient achieves the maximum value at the specimen surface, and the spot where the normal temperature gradient achieves the maximum value move gradually toward the specimen interior with the time. In circumferential orientation, the maximum tangential temperature gradient occurs at the edge of laser irradiation, where the spatial distribution of laser intensity varies sharpest, and the maximum normal temperature gradient occurs at the center of the laser irradiation.