针对内通道传输过程中激光束相位特性的变化,建立了内通道中光场-流场的耦合仿真模型,通过引入湍流相位屏模拟了内通道中湍流扰动对传输光束波前相位的影响。在此基础上,定量计算了不同轴向风速条件下内通道传输光束的波前相位特性,并结合自适应波前校正模型,分析了激光束经内通道传输后的波前校正效果。研究结果表明,随着轴向风速的增大,激光束波前相位中的高频成分呈现出先增大后减小的趋势,经自适应波前校正后的光束质量也呈现出类似趋势,且当轴向风速约为0.65 m/s时畸变波前中的高频成分最多,经波前校正后的光束质量最差。该模型能够为激光控制系统的设计和性能评估提供一定参考。

According to the phase distortion of laser beam in inner propagation process, a simulation model for the laser beam interacting with the fluid of the inner channel was established, in which the phase distortion caused by the thermal effects was taken into account and the influence of turbulence disturbance of the inner channel on the wavefront phase was simulated by introducing the method of phase screen. The phase characteristics of laser beams propagating through the inner channel on the conditions of different axial wind speeds was discussed in detail in terms of wavefront power spectral density, and the correction effect of laser beam propagation through the inner channel was further analyzed using the adaptive wavefront correction model. The results show that, with the increase of axial wind speed, the high frequency component of the wavefront phase increases at first and then decreases, and the beam quality gets worse at first and then becomes better. Particularly, the high frequency component of the wavefront phase increases most quickly and the beam quality degrades most significantly when the axial wind speed is about 0.65 m/s. This model provides a qualitative reference for the laser beam control system design and performance evaluation.