地面突风对通航飞行器的影响及数值模拟研究

Influence of Gust on Flight in Navigable Airport and Its Simulation

突风一直以来都是危及飞行安全的重要气象要素之一,造成国民经济和人民生命财产的损失。利用常规观测资料、ADWR-X多普勒气象雷达资料和ERA5逐小时再分析资料,对四川盆地西部一次爆发性大风过程中风场的精细化特征、成因及对飞行的影响进行诊断和模拟研究,结果表明:此次大风过程风速增长快,爆发性强。地面风速自午后开始出现4次波动,且每一次波动期间风速峰值呈增加趋势,时间呈缩短趋势。由于第4次波动风速呈爆发性增加,最大瞬时风达到了16.1 m/s,地面风速脉动值超过5 m/s,致使跑道区域内流场的不稳定性增加,起降跑道侧风值超过了中小型飞行器的起降标准。高空动量下传对本次大风过程中风速的爆发性增加起主导作用。中层强偏南气流与低层偏北急流配和,中层辐合以及低层辐散下沉的垂直结构使得低层下沉气流异常强劲,将900~850 hPa的大风核快速向地面传导。通过天气研究与预报(weather research and forecasting,WRF)模式四重嵌套对本次过程进行模拟,表明WRF对盆地西部冷空气补充南下引起的在风速演变趋势、风速最大值和大风影响时段的风向有较好的模拟能力,对飞行起飞和着陆有一定的参考价值。

Sudden winds have always been one of the important meteorological factors that endanger flight safety,causing losses to the national economy and people s lives and property.By using conventional observation data,ADWR-X Doppler weather radar data and ERA5 hourly reanalysis data,a diagnostic and simulation study was carried out on the refined characteristics,causes and impact on flight of the wind field during an explosive gale in the west of Sichuan Basin.The results show that the ground wind speed fluctuates four times since the afternoon,and the peak value of wind speed increases during each fluctuation,while the time decreases.Due to the explosive increase of the fourth wave wind speed,the maximum instantaneous wind speed reaches 16.1 m/s,and the fluctuation value of ground wind speed exceeds 5 m/s,which leads to the increase of the instability of the flow field in the runway area,and the value of the crosswind on the takeoff and landing runway exceeds the takeoff and landing standards of small and medium-sized aircraft.The downward propagation of upper air momentum plays a leading role in the explosive growth of wind speed during this gale.The gale occurs in the process of the transition from the upper warm advection to the cold advection.The strong southerly flow in the middle layer is matched with the northward jet in the lower layer.The vertical structure of the convergence in the middle layer and the divergence and subsidence in the lower layer makes the downward flow in the lower layer extremely strong,and the 900~850 hPa gale core is rapidly transmitted to the ground.Using the ERA5 reanalysis data as the initial field driven weather research and forecasting(WRF)model,the local process is simulated through quadruple nesting,which shows that WRF has a good simulation ability for the north gale caused by the cold air supplement from the west of the basin in the wind speed evolution trend,maximum wind speed and wind direction during the influence period of strong winds,which has an important reference value for flight support.