细长圆锥前体非对称涡流场的等离子体控制

应用一对单介质阻挡放电(SDBD)等离子体激励器对顶角为20°的圆锥-圆柱组合体圆锥段分离涡流场进行了主动控制试验研究。试验在3.0m×1.6m低速低湍流度风洞中进行,迎角为45°,基于圆锥段底面直径的雷诺数为5×104。流动控制分为等离子体激励器关闭,左舷或右舷等离子体激励器分别开启,左右舷等离子体激励器占空循环3种模式。试验结果包括7个测量截面上的周向压力分布以及积分得到的截面当地力和力矩以及圆锥段力和力矩。研究结果表明,在圆锥头部尖端处迎风面两侧对称放置一对SDBD等离子体激励器,采用合适的激励器形式,并通过适当的电学参数,可以实现对细长旋成体侧向力和力矩的比例控制。通过对模型及等离子体激励器制作的改进,相对于前人相应的研究结果,本文中侧向力和力矩随占空比变化的线性度得到了改善。

Control of Asymmetric Vortices over a Slender Conical Forebody Using Plasma Actuators

An experimental study of the active control of vortices over slender forebodies is performed on a 20° circular-cone-cylinder model using a pair of single-dielectric barrier discharge (SDBD) plasma actuators. The tests are carried out in a 3.0 m×1.6 m low-turbulence and low-speed wind tunnel at an angle of attack of 45°. The Reynolds number based on the base diameter of the circular cone is 5×104. The results consist of measu-rements of circumferential pressure distributions over seven stations along the cone under three different modes of controls: both plasma-off, plasma-on port or starboard, and plasma duty-cycle actuations. The local cross-sectional and overall side forces and moments over the cone are calculated from the measured pressures. The results indicate that it is possible to achieve linear proportional control of the lateral forces and moments of the slender body by the duty-cycle plasma flow control technique with appropriately designed plasma actuators and selected electric parameters. The linearity of the controlled lateral forces and moments with respect to the duty cycle is improved over previous studies because of the improved design of the actuators.