Effects of Plasma Actuator Discharge on Lift-Enhancement and Flow Patterns of Flying Wing Aircraft

等离子体激励对飞翼布局飞行器增升及流态影响

¹ Beijing Electro-Mechanical Engineering Institute, Beijing 100074, China
² College of Aerospace Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China

Received: 9 September 2017

Abstract

The nanosecond pulsed plasma discharge actuator is used on a flying wing aircraft. At the angles of attack rang from -4° to 28°, the impact of plasma actuator arrangement position and discharge frequency on lift-enhancement effect is tested. Oil flow visualization is used to investigate the surface flow pattern varies with angles of attack for the plasma actuator turned on and off. The result indicates that lift-enhancement can be achieved through the actuator discharges at large angles of attack on flying wing aircraft. The arrangement position and discharge frequency both have a significant impact on lift-enhancement effect. The actuator which arranged at the leading edge of the aircraft could get the best lift-enhancement effect. There exists an optimal discharge frequency, flow separation under this frequency can be effectively suppressed, which results the best lift-enhancement effect. The flow visualization test shows that the control mechanisms of the plasma actuator are to inject energy to the shear layer, thus increased the vortex strength. The vortices strengthen the mixing of the outer high-speed fluid with inner low-speed fluid, which effectively restrains the separation.

摘要

将纳秒脉冲等离子体激励器应用于飞翼布局飞行器上，在-4°~28°攻角范围内，开展了激励器布置位置和放电频率对增升效果的影响研究，采用油流显示方法分析了不同攻角下激励器作用与否表面流态随攻角的演化规律。研究结果表明，等离子体激励器通过放电能够在大攻角时实现飞翼布局飞行器的增升；布置位置和放电频率对增升效果的影响较大，布置于飞行器前缘的激励器能够获得最佳的控制效果，存在最优的放电频率，在该频率下流动分离被有效抑制，增升效果最佳；油流显示结果表明激励器对分离流的控制机理在于施加激励后对剪切层注入能量，增加了分离涡强度，促进了剪切层外高速与内部低速气流的掺混，有效抑制了分离的发生。