天文选址的决策和激光传输系统的设计和应用需要掌握大气光学湍流的时空变化规律。利用HTP-2型温度脉动仪测量近地面湍流,用大气相干长度仪测量整层湍流积分效应。分析折射率结构常数C2n的实测数据,得到近地面光学湍流月平均和季平均的变化规律。分析了早晚两个"转换时刻"不同参数的变化规律。根据广义Hufnagel-Valley模式反演得到夜间、白天及"转换时刻"整层湍流廓线,比较了不同时刻湍流廓线的特点。在连续多年实测数据的基础上所得结论全面可靠,具有重要的工程参考价值。
Spatio-temporal evolution of optical turbulence is important for site-testing and optimizing the performance of adaptive optical systems. Measurements were taken over three years using surface layer atmospheric parameter system and differential image motion monitor. Microthermal sensors measured structure constant of refractive index and differential image motion monitors measured atmospheric coherent length and isoplanatic angle. Analysis of structure constant of refractive index showed the monthly and seasonal evolution of surface optical turbulence. Different parameters were analyzed during inversion time.The vertical profile of atmospheric structure constant of refractive index was gained based on Hufnagel-Valley mode1 for night,day and inversion time and different characters were found for different profiles.Based on longtime experiments, the results are credible and valuable for engineering application.