通过分析不同情况下激光与固态靶、气化物质的作用机理, 利用激光体烧蚀模型, 采用流体力学理论和1维Lagrange有限差分的计算方法, 对真空条件下不同激光参数下气化物质对靶产生冲量的过程进行了数值模拟, 模拟计算结果与实验测量结果、Phipps定标关系符合较好。计算结果表明, 在等离子体的情况下冲量耦合系数随着激光强度增大而减小。

Analyzing the interaction mechanism of laser with target and vaporized target material, a one-dimensional bulk absorption model to simulate the solid target ablated directly by the laser beam is presented, numerical calculation of impulse acting on the target in vacuum with different laser parameters is performed with fluid dynamics theory and 1D Lagrange difference scheme. The calculated values of the impulse coupling coefficient are in good agreement with the experimental results and Phipps’s empirical value. From the calculated results, the impulse coupling coefficient decreases with the increment of laser intensity when the laser pulse generates a plasma.