不同形式等离子体激励对细长体分离涡的控制

Flow control over a slender conical forebody by different plasma actuations

应用一对单介质阻挡放电(Single-Dielectric Barrier Discharge,SDBD)等离子体激励器对20°顶角圆锥前体分离涡流场进行了主动控制实验研究。在模型尖端处表面上布置两组不同形式的介质阻挡放电等离子体激励器,通过左、右舷等离子体激励器分别开启来实现对圆锥前体非对称涡流场的控制。对圆锥前体8个测量截面的周向压力分布进行了测量,并对相应的缩比模型进行了固定截面的粒子图像测速实验(Particle Image Velocimetry,PIV)。静态压力测量实验在3.0m×1.6m低速低湍流直流闭口风洞中进行,粒子图像测速实验在0.6m×0.5m低速直流开口风洞中进行,迎角固定在45°。研究结果表明:对两种不同形式和布置位置的激励器,当左、右舷激励器分别开启时,压力分布均出现了明显的变化,显示出等离子体激励对非对称分离涡流场可以进行有效控制;顺吹型和逆吹型等离子激励器对流场产生影响的效果和机理有所不同,应用顺吹型等离子体激励器时的流动控制有效风速要高于使用逆吹型等离子体激励器。

An experimental study of the vortex flow control over slender forebodies was performed on a 20° circular-cone-cylinder model using a pair of Single-Dielectric Barrier Discharge （SDBD） plasma actuators. Two different pairs of Single Dielectric Barrier Discharge （SDBD） plasma actuators are installed near the tip on the surface of the model. Three modes of operation of the actuators are defined. The plasma off mode cor- responds to the case when neither the two actuators is activated, Port on and starboard on modes refer to the condition when the port side and the starboard side actuator is activated respectively. The pressure measure- ment test consist of measurements of circumferential pressure distributions over eight stations along the cone and were carried out in a low-turbulence 3.0m× 1.6m low-speed wind tunnel with a closed test section. The PIV measurement test consist of measurements the cross flowfield velocity over one station on a scaled mod- el, the test was carried out in a 0.6mX0.5m low-speed open test section wind tunnel. The test angle of at- tack is 45~. The experiments indicate that an effective control on vertex flow over the conical forebody can be achieved using plasma actuation. The higher wind speed can be achieved by adjusting the position and direc- tion of the plasma actuations.