侧滑角对大长细比鸭式布局弹箭俯仰操纵性的影响

Influence of Sideslip Angle on Pitching Maneuverability of Canard Configuration Missiles with Large Length to Diameter Ratio

大长径比鸭式布局制导弹箭进行倾斜转弯控制时,受侧滑角、攻角和滚转角影响,鸭舵产生的斜吹洗流会引起尾翼和弹身产生额外的面外力和力矩。因此为研究侧滑角对大长细比弹箭操纵性的影响,将流场域划分六面体-多面体网格,采用CFD方法对鸭式布局弹箭在不同攻角、马赫数、舵偏角和侧滑角下的气动特性进行了数值模拟,得到了弹箭气动特性的变化规律,绘制出了弹箭的流线图、涡量图和压力云图,进行流场分析研究。利用风洞实验获得相关空气动力学参数,对实验结果作对比分析,发现风洞实验与数值模拟得到的结果都有较高的吻合度,验证了数值模拟方法的可行性。研究表明多数情况下侧滑角不为零时,由于弹箭的弹体较长,鸭舵的洗流向弹体一侧偏移,使得鸭舵的洗流对部分尾翼没有产生干扰,尾翼的当地攻角增大,尾翼法向力变大,弹箭的压心后移,平衡攻角减小,静稳定度变大,进而弹箭的俯仰操纵效率降低;而在少数情况下弹箭尾翼当地攻角却降低,尾翼法向力有所降低,静稳定度变小,弹箭的操纵效率有所提高。

Due to the influence of sideslip angle,attack angle and roll angle,the oblique flow of canard-type missile with large length-diameter ratio generated by the canard rudder is very serious when the bank-to-turn control is carried out.Additional out-of-plane forces and moments of the missile may be caused since the flow around the tail and body is asymmetric.Therefore,in order to study the effect of sideslip angle on the aerodynamic characteristics of missiles with large length-diameter ratio,hexahedral polyhedral grids of the flow field domain were generated.Numerical simulation was conducted on the aerodynamic characteristics of canard shaped projectiles at different attack angles,Mach numbers,rudder angles,and sideslip angles.The variation law of the aerodynamic characteristic,streamline,vorticity,and pressure cloud maps of the projectiles were obtained.Wind tunnel experiments of the missile was carried out.The experimental results were compared with simulation data,which verified the feasibility of the CFD method.The research shows that the downwash flow of the canard-rudder is shifted to the side of the affecting by the body sideslip angle and long missile body.The washing flow of the canard rudder shows little effect on the tail.With the increases of local angle of attack of the tail,the normal force of the tail increases too.Therefore,the pressure center of the missile shifts back,the equilibrium angle of attack decreases,the static stability margin becomes larger,and the pitch maneuvering efficiency of the missile decreases.While,the local angle of attack of the tail and the normal force of the arrow are reduced in a few cases,result in reducing the static stability and improving the maneuvering efficiency of the arrow.