支杆-钝头体带攻角流场和“军刺”挡板作用研究

INVESTIGATIONS ON SPIKED BODY FLYING WITH ANGLE OF ATTACK AND MECHANISMS OF ACTION BY BAYONET SHAPED PLATES

通过三维N-S方程的数值求解,研究了支杆-钝头体结构在10°攻角Mo_∞=6.0飞行条件下的流场结构和特点,指出其气动力特性恶化的原因,提出采用"军刺"挡板改善流场和气动力特性,并通过对比两种不同挡板作用下的流场和气动力特性变化分析其作用机理,发现"军刺"挡板结构分割流场抑制三维效应形成的周向流动,迎风面形成稳定的回流区和剪切层结构,将迎风面锥激波推离轴线,降低钝头体肩部流动结构相互作用强度,并在一定程度上缓解背风面流动干扰,明显改善支杆-钝头体带攻角飞行时的气动力特性.

Three-dimensional Navier-Stokes equation was numerically solved to investigate the flow structure and characteristics of spiked body flying at M∞= 6.0 with 10° angle of attack. With reasons for the deterioration of aerodynamic force pointed out, bayonet shaped plates were set to improve the flow field and aerodynamic characteristics. By comparing the actions of plates with two different configurations, the mechanisms for the bayonet structure can be stated as formation of circumfluence and shear layer at windward side due to the plates splitting the flow field and depressing flow in toroidal direction, which will drive conical shock to move away from axial line, lower the strength of interaction between flow structures around the blunt body and weaken the perturbation at leeward side.