过山气流低空风切变对野战火箭弹弹道特性影响分析

针对过山气流低空风切变的流动特点,基于位势流动理论,在地面坐标系上建立考虑地面摩擦及背风旋涡的过山气流三维风场分布模型。结合六自由度刚体弹道模型,以某122mm尾翼火箭弹为例,仿真分析了野战火箭弹在主动段受过山气流风切变影响的弹道特性变化。结果表明,过山气流低空风切变对野战火箭弹的飞行时间、射程、侧偏,落速及角运动均产生较大影响,其中对弹箭横向运动的影响较为显著;风场强度与野战火箭弹受风场的影响程度正相关;野战火箭弹在迎风坡与背风坡发射时,弹道特性的变化规律相反,且背风坡处发射时弹道特性的变化更明显;中低射角范围内,增大野战火箭弹的射角能够降低过山气流低空风切变对射程的影响,但侧偏所受的影响会相应增大。

An Analysis of Influence of Airflow over Mountain Wind Shear on Ballistic Performance of Rockets

In view of the flow features, a three dimensional wind field model of airflow over mountain in consideration of the ground friction and the leeward vortex are established based on the theory of potential flow. Taking a certain empennage rocket of 122 mm as an example combined with 6 DOF ballistic model, this kind of empennage rocket is studied on its ballistic performance of prior trajectory influenced by the airflow over mountain wind shear. The results show that the airflow over mountain wind shear has a certain impact on the flight time, the range, the side-slip, the falling velocity and the angular motion of a rocket, particularly on the lateral movements of a rocket. The wind field strength is positively related to the influences on a rocket by the airflow over mountain; The changing regularity of ballistic performance when the rocket launched on the windward slope is opposite to that of leeward slope and the ballistic performance is more affected when a rocket is launched on the leeward slope. Within the range of middle low elevation, the incremental elevation of a rocket is enabled to influence on the range of a rocket by the airflow over mountain, meanwhile the influence on the side slip may increase correspondingly.