论文部分内容阅读
采用大涡模拟方法计算了来流速度为0.4 Ma情况下球/柱形结构附近的流场,根据密度数据计算了光程差及气动相屏,并研究了尾流对激光传输的影响。结果表明:光程差空间均方根的时间平均值随发射角增大而增大,发射角从120°增加到148°时,其数值从0.11μm增加到0.28μm;光程差空间均方根随时间变化剧烈,发射角为148°时,其时间均方根可达0.04μm;球/柱尾流对激光传输有很大影响,发射角为148°情况下,Strehl比的时间平均值为0.33,并且Strehl比的时间平均值随发射角的增大而减小,发射角从120°增加到148°过程中,Strehl比的时间平均值减小了59%;Strehl比随时间变化剧烈,其时间均方根大于0.05。
The large eddy simulation method was used to calculate the flow field near the ball / column structure with a flow rate of 0.4 Ma. The optical path difference and the aerodynamic screen were calculated based on the density data. The effect of wake flow on laser transmission was also studied. The results show that the average value of the root mean square of the optical path difference increases with the increase of the emission angle. When the emission angle increases from 120 ° to 148 °, the value increases from 0.11μm to 0.28μm. The root mean square of time was up to 0.04μm with the emission angle of 148 °. The ball / column wake had a great influence on the laser transmission and the average Strehl ratio at the emission angle of 148 ° Was 0.33, and the time average of Strehl ratio decreased with the increase of the angle of incidence. The mean value of Strehl ratio decreased by 59% when the angle of emission was increased from 120 ° to 148 °. The Strehl ratio changed drastically with time , The root mean square of its time is greater than 0.05.