脉冲激光辐照靶材破坏效果最优条件研究

Study on the Optimum Condition of Target Damage Effect Irradiated by Pulsed Laser

为解析脉冲激光对靶材的破坏效果与激光各参数之间的关系,提出了一种基于数值计算方法的仿真模拟方案,开发了一套脉冲激光辐照靶材的热-力效应数值仿真软件。采用对照法,分别对激光功率、激光能量、激光光斑大小、脉冲宽度和间歇时间等五个参量进行控制,对比不同参数条件下激光破坏靶材的效果,讨论并得出了优化脉冲激光破坏靶材的方法。仿真结果表明,激光能量和功率密度与破坏效果之间是非线性关系,随着二者的增加,对破坏效果的边际加强效果减弱;随着间歇时间的增加,破坏效果先增大后减小。对于确定的靶体目标,通过增加脉冲激光的输出能量和功率密度,减小光斑半径,调整脉冲间歇时间,可以使得脉冲激光辐照靶材的破坏效果达到最佳。

In order to analyze the relationship between the effect on the target and the parameters of the pulsed laser,a simulation scheme based on numerical calculation method is proposed in this paper.Furthermore,a set of numerical simulation software for thermal force effect of laser irradiated target is developed.The laser power,laser energy,laser spot size,pulse width and interval time are controlled respectively by using contrast method.The effect of laser damage on the target under different parameters is compared,and the optimum conditions for the damage of the target by the pulse laser are discussed and obtained.As shown by the simulation results,there is a nonlinear relationship between the laser energy and the power density and the damage effect.The marginal enhancement of the damage effect is weakened as they increase.With the increase of the interval time,the damage effect increases first and then decreases.The destructive effect of the laser irradiated target can be reached to the best by increasing the output energy and power density,reducing the radius of laser spot and selecting reasonable pulse interval time within the limits allowed.