风对光束控制系统内热效应的抑制作用

 用光强沿x轴方向呈线性变化的方形环状光束模拟高功率激光，利用自编四维仿真程序对高功率激光在光束控制系统中的传输作了详细的数值计算研究。结果表明：热效应使远场光束的峰值光强和可聚焦能力下降。入射光强的非均匀分布进一步降低峰值光强和可聚焦能力，导致远场光束重心和峰值光强位置移动，并产生像散。光束的非均匀程度越高，远场光束质量越差。横向风和轴向风对热效应均有抑制作用。然而，轴向风不会引起远场光束重心偏移和像散，但是轴向风比横向风建立稳态所用时间更长。

Suppression of the thermal effect within a beam control system in the presence of wind

An annular square intensity distribution with linear non-uniformity in the x direction is used to model the high-power laser, a detailed numerical simulation is performed to study the high-power laser propagation in a beam control system by means of a four-dimensional simulation code. It is shown that the thermal effect decreases the peak intensity and beam focusability in the far field. The non-uniformity of the initial beam results in a further decrease of the peak intensity and beam focusability, leads to a shift of the center of beam gravity and peak intensity, and astigmatism in the far field. The transversal wind and axial wind both suppress the thermal effect. The axial wind does not cause a shift of the center of beam gravity and astigmatism in the far field, but it takes a longer time for a steady state than the transversal wind does.