双旋弹道修正弹弹体非对称载荷的数值研究

固定鸭舵双旋弹道修正弹的弹体受到鸭舵非对称尾流的影响，其载荷具有非对称特性。为了研究该非对称特性，通过计算流体力学(CFD)仿真和风洞实验的结果对比验证CFD方法的有效性。对0°舵偏、2°舵偏、4°舵偏的双旋弹道修正弹模型在多马赫数、多攻角下进行CFD仿真，并通过绘制鸭舵尾流的流线图和弹体压力系数云图对流场进行定性分析，通过对比弹体截面压力系数和弹体法向力、侧向力系数对弹体受力的非对称性进行定量分析。结果表明： 0°舵偏模型的弹体压力系数呈面对称，2°舵偏模型、4°舵偏模型弹体压力系数呈非对称；在给定马赫数下，3种模型弹体法向力系数随攻角变化的曲线高度重合； 0°舵偏模型的弹体侧向力系数在0附近，2°舵偏模型、4°舵偏 模型的弹体侧向力随攻角近似线性变化，随马赫数先增大、后减小；给定攻角时，4°舵偏模型对应曲线峰值约为2°舵偏模型的2倍。

Numerical Study of Asymmetrical Load on the Body of Dual-spin Projectile

The load on dual-spin projectile's body has an asymmetrical characteristic because of the influence from asymmetrical wake flow of canards. The asymmetrical load on the projectile body is studied. The results form computational fluid dynamics (CFD) simulation and wind tunnel test are compared to prove the effectiveness of the CFD method. The dual-spin projectile models with control surface angles of 0°, 2°and 4° are simulated at various Mach numbers and angles of attack. The flow field is qualitatively analyzed by drawing the streamline diagrams of tail flow of canards and the pressure coefficient contour map of projectile body. The asymmetry of force of the projectile body is quantitatively analyzed by comparing the pressure coefficient of body section and the lateral force coefficient of body. The result shows that the body section pressure coefficient of the model with control surface angle of 0° is symmetrical, and the body section pressure coefficients of the model with control surface angles of 2°and 4°are asymmetrical. The projectile body's normal force coefficient curves of three models coincide with each other as the change in the angle of attack at a given Mach number; and the lateral force coefficient is near 0 for the model with control surface angle of 0°, but is approximately linear with the angle of attack for the models with control surface angles of 2° and 4°, and is first ascended and then descended with the Mach number. When the angle of attack is given, the peak value of the model with control surface angle of 4° is about 2 times that of the model with control surface angle of 2° .