机构地区: 南京理工大学动力工程学院瞬态物理国家重点实验室
出 处: 《工程力学》 2016年第6期250-256,共7页
摘 要: 超声速弹箭表面的流体分离是影响飞行稳定的主要影响因素之一。研究表明,微楔涡流发生器可有效控制超声速流体边界层的流动分离。该文基于制式122火箭弹,通过在弹肩前端安装微楔来研究边界层流动分离控制对火箭弹气动性能的影响。运用DES方法数值模拟了122火箭弹在有无加装微楔条件下的流场变化,对比分析了微楔对弹体表面边界层结构以及弹气动数据的改变,讨论了微楔对弹的气动力及稳定性作用。数值结果表明,微楔可以抑制弹体表面流体分离,提高火箭弹的升力及俯仰力矩,减小马格努斯力矩,有利于提高其飞行稳定性及射击精度,可为相关旋转火箭弹的改进提供指导。 Fluid separation on the surface of supersonic projectiles and missiles is one of the main factors influencing their flight stability. Studies have shown that micro-wedge vortex generators (MVG) can effectively control the flow separation of the supersonic boundary layer. In this paper, based on the original standard 122 finned projectile, MVG's were mounted at the projectile shoulder to investigate the effect of separation control on the aerodynamic characteristics of the projectile. Numerical simulations of the flow fields of 122 standard finned projectiles with and without micro wedges were performed with the DES method, the modifications of the boundary layer structures and aerodynamic data for two cases were compared and discussed, and the influence of micro-wedges on projectile aerodynamic forces and stability have also been investigated. Numerical results show that the micro wedges can inhibit fluid separation on the projectile surface, improve the projectile lift and pitching moment, and decrease the Magnus moment, as a result improving the flight stability and firing accuracy, which can provide guidance for the improvement of spinning projectiles.
领 域: [航空宇航科学与技术]