钝头战术导弹大攻角流动特性数值模拟

Numerical simulation of the aerodynamic characteristics of blunt-head missile under large attack angles

对具有钝头和小展径比外形特点的战术导弹进行了大攻角流动数值模拟与分析。着重分析了大攻角下弹体轴向各横截面上的压力分布、导弹背部和弹翼表面的气流分离形态及其随攻角的变化。通过模拟发现了钝头弹大攻角分离的一些重要特点,例如,与常见的尖锥体导弹背部的非对称分离涡不同,钝头导弹背部的分离涡是对称的;在弹翼以前不存在纵向分离,只有横向分离;分离区随着攻角的增加而扩大,但分离区起点的位置却基本上不变等。这些结果为这类导弹的设计提供了重要依据。

The numerical simulation and analysis of the aerodynamic characteristics under large attack angles are made for a tactical missile with the typical geometry feature of this type ： blunt head and small ratio of diameter to span. Emphatic analysis is made on the pressure distribution over the cross sections along the missile axis, the flow separation on the back side of the missile body and the wing surface, as well as their variations with the attack angle. Some important characteristics of the flow separation on the blunt-head missiles under large attack angles have been discovered through CFD simulation. For example, quite different from the unsymmetric flow separation on the backside of the cone-head missile, the flow separation of a blunt-head missile is symmetric; it happens only in the cross direction not the axial direction; the separation zone spreads out with the increasing attack angle of coming flow, but the position of the initial separation point changes slightly; and etc.. These simulation results provide important basis to the design of the missiles of this type.