在相对论性激光-等离子体系统中模拟激光参数对等离子弧柱形态的影响

基于相对论性激光-等离子体动力学理论和PIC方法建立了激光入射等离子弧柱的模型,该模型描述了激光入射等离子弧后粒子的运动,并模拟了弧柱形态的变化。通过改变激光的平均功率、脉冲宽度以及重复频率,模拟等离子弧柱形态变化,得到的激光参数对等离子弧柱形态的影响规律。通过控制弧柱的直径可以提高材料的熔积性能。计算结果表明增大激光平均功率、脉冲宽度,可以更深地压缩等离子弧;但是,重复频率的影响则会出现波动现象。激光等离子复合加工更适合于精细加工。

Influence of Laser Parameters on Plasma Arc Beam Shaping in the Relativistic Laser-plasma System

A 2D mathematical model was developed to investigate laser-plasma interaction based on the theoretic-of relativistic laser-plasma and PIC approach, presenting the movement of particles when laser enters into plasma arc beam, together with the simulation of diversification-of arc beam shaping. The laser parameters, such as average power, pulse width and pulse repetition frequency were changed in order to simulate diversification-of arc beam shaping. The results indicated that the arc beam would be compressed when the laser average power or the laser-pulse width was increased. But the influence of pulse repetition frequency was complicated.