1053nm脉冲激光对铝合金/水结构辐照效应

Effects of laser irradiation on aluminum alloy tank containing water

使用1 053 nm脉冲激光分别辐照铝合金单板和铝合金/水结构,通过表面形貌观察、温度场分析、熔穿时间测量等手段,分析了水的存在对铝合金壳体烧蚀的影响。运用有限元软件ANSYS,建立了脉冲激光辐照下单板及结构温度变化的数值模型,计算了铝合金表面熔凝区域的尺寸,并与实验结果进行了对比。结果表明:在相同的实验条件下,辐照8个激光脉冲时,铝合金单板即被熔穿,而辐照10个脉冲后铝合金/水结构仍未发生熔穿,且结构中铝合金表面的熔凝区域要小于单板情形中的熔凝区域,这表明水的存在对延缓铝合金板的烧蚀有较大的作用。对于单板情形,计算结果与实验结果符合较好,而对于铝合金/水结构情形,数值模拟放大了铝合金壳体的温升,这主要是因为数值模拟程序未考虑水的对流及沸腾换热对计算结果的影响。

Experimental measurement and numerical simulation are employed to study the effects of laser irradiation on aluminum alloy tank containing water.Firstly,by analyzing the surface pictures and measuring the temperature histories,the effects of water on the ablation of aluminum alloy plate irradiated by 1 053 nm pulsed laser are investigated.The results show that heat conduction and convection play a very important role in the ablation of the aluminum alloy plate.When the tank is empty,the aluminum alloy plate is melt through after eight laser pulses irradiation.And when the tank is filled with water,the aluminum alloy plate has not been melt through after ten laser pulses irradiation.Then,a numerical model is presented to calculate the temperature distribution of the aluminum alloy tank,and the dimension of the region that has melted is obtained.The difference between the numerical result and the experimental result is not apparent when the tank is empty,but when the tank is filled with water the difference is a little large.The reason is that the natural convection and boiling of water are not considered in the numerical model.