采用计算流体力学(CFD)数值模拟方法,研究战术导弹大迎角状态下涡破裂导致滚转力矩随迎角非线性增长引起舵面控制能力不足的现象。首先通过标准模型的数值分析,验证了所采用的CFD方法具有三角翼前缘涡破裂现象的捕捉能力;然后采用雷诺平均Navier—Stokes方程对某“++”字正常布局导弹构型(含弹翼、弹身、尾舵和整流罩等)进行了数值模拟,结果显示亚声速状态下滚转力矩在迎角大于20°时出现非线性增长,导致全动尾舵的滚转控制能力不足。通过分解各部件对滚转力矩的贡献,并分析流场结构,探明了该现象发生的流动机理,其主要原因是:随着迎角的增长,弹体迎风面的尾舵前缘涡首先发生破裂,导致其平衡诱导滚转力矩的作用被削弱。
The nonlinear effect of a tactical missile's rolling moment at high angles of attack is numerically studied in the present paper. The capability of the computational fluid dynamics (CFD) scheme in capturing leading edge vortex and its breakdown is verified by a standard delta wing model. A missile in normal configuration in "+ +" layout, consisting of wings, body, tail rudders and cable fairing, is numerically investigated by solving Reynolds averaged Navier-Stokes equa-tions. The results show that the nonlinear rising of the rolling moment appears after the angle of attack becomes greater than 20°, leading to the inadequacy of the rudder's roll control ability. The mechanism of this phenomenon is obtained through the decomposition of the contributions of each component to the rolling moment as well as an analysis on the flow structure. With the increase in the angles of attack, the leading edge vortex of the tail rudder at the windward side breaks first, which weak-ens its function of restraining the rolling movement.