飞翼模型微秒脉冲等离子体控制低速风洞试验研究

Study of Low Speed Wind Tunnel Test Using Microsecond Pulsed Plasma Actuation on Flying Wing Model

关键词:  流动控制  等离子体  飞翼  流动分离  风洞试验

Key words:  Flow control  Plasma  Fly wing  Flow separation  Wind tunnel test

摘要:

为改善飞翼模型低速、大迎角气动特性，在试验段截面为4.5m×3.5m的低速生产型风洞中开展了大展弦比飞翼模型微秒脉冲等离子体流动控制的试验研究，所用的飞翼模型展长为2.4m，展弦比为5.79，试验研究采用了测力和PIV（Particle Image Velocimetry）两种试验方法。通过测力试验研究了等离子体激励位置和激励频率对飞翼模型失速特性的影响，通过PIV流动显示试验给出了等离子体对翼面流场结构的影响。试验研究表明：等离子体控制能显著改善大展弦比飞翼模型低速大迎角下的气动特性，激励位置和激励频率对流动控制效果具有较大影响；等离子体激励位置在机翼前缘驻点附近、激励频率为100Hz时控制效果最好；试验风速V=70m/s（Re=2.61×10⁶），等离子体激励的峰峰值电压为10kV时飞翼模型的最大升力系数提高20.51%，失速迎角推迟6°。

Abstract:

In order to improve the aerodynamic performance of a flying wing model with a 2.4m span and 5.79 aspect ratio under large angle of attack and low speed, an experimental study of microsecond pulsed dielectric discharge plasma actuator control was carried out combining force measurement and PIV (Particle Image Velocimetry) in the low speed wind tunnel with a 4.5m×3.5m test section. The effects of plasma discharge position and frequency on stall were studied by means of force measurement, PIV test revealed the influence of plasma actuation on wing surface flow field. The test results show that plasma actuation can significantly improve the aerodynamic performance of flying wing model under large angle of attack and low speed, plasma discharge position and frequency have significant impact on the control effect. The best control effect is obtained when the plasma actuator is placed near the wing stagnation point and the discharge frequency is 100Hz. When the wind speed is 70m/s （Re=2.61×10⁶） and the discharge peak to peak voltage is 10kV, the maximum lift coefficient increased by 20.51%, and the stall angle of attack is postponed by 6°.