临近空间风切变特性及其对飞行器的影响

基于MERRA再分析资料的风场数据，根据数理统计理论，对酒泉（39.1°N，98.5°E）上空临近空间的20~78 km的大气风场进行了风切变特征分析，并分析了临近空间风切变对飞行器的影响。研究表明，临近空间最多风向在1月和10月为西风，7月为东风，4月在50 km以下为西风，以上为东风；99%概率最大风速在1月最大；最大风引起的风切变存在一定的高度范围。根据最大风和最小风给出了综合矢量风。此外发现临近空间风切变对飞行器产生的风攻角显著，对马赫数为3、5和8的飞行器产生风攻角在69 km最大，分别为8.5°、5.1°和3.2°。 

Wind shear characteristics in near space and their impacts on air vehicle

Based on the near-space wind field data from MERRA reanalysis data, the seasonal variation of atmospheric wind field at 20-78 km is investigated. The characteristics of wind shear over Jiuquan (39.1°N, 98.5°E) are analyzed by the method of mathematical statistics. Moreover, the effect of wind shear on the near-space aircraft is studied. The results show that the wind in near space is eastward in January and October, westward in July, and eastward (westward) below (above) 50 km in April. The maximum wind speed occurs in January with 99% probability and the shear induced by the maximum wind has a certain height range. The synthetical wind vector is also given by the maximum wind and minimum wind. In addition, the wind attack angle of the near-space aircraft caused by the wind shear is significant. The wind attack angles for air vehicle with Mach numbers 3, 5 and 8 are biggest at 69 km, which are 8.5°, 5.1° and 3.2° respectively.