High-lift airfoil separation with dielectric barrier discharge plasma actuation
High-lift airfoil separation with dielectric barrier discharge plasma actuation
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DOI：
10.2514/1.j050452
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发表时间：
2010-12
期刊：
影响因子：
2.5
通讯作者：
J. Little;M. Samimy
中科院分区：
文献类型：
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作者：
J. Little;M. Samimy
在雷诺数为240，000（15 m/s）和750，000（45 m/s）之间，研究了单介质阻挡放电等离子体激励器控制高升力翼型偏转襟翼湍流边界层分离的效果。介质阻挡放电等离子体致动器的动量系数比通常用于此类研究的动量系数低约一个数量级，但控制当局仍然通过放大襟翼肩部的自然涡脱落来实现，这促进了自由端和分离区域之间的动量传递。这增加了襟翼上的动态载荷，并进一步组织了尾流中的湍流波动。测得的升力增强主要是由于整个模型周围增加的环量所产生的上游效应，而不是由于偏转襟翼表面的完全再附着。通过不稳定性放大的升力增强被发现对攻角的变化相对不敏感，只要分离位置和基本动力学不改变。用于激励低频扰动与高频等离子体载波信号的调制波形对致动器性能有相当大的影响。随着雷诺数和襟翼偏转的增加，控制权降低，突出了进一步改进等离子体致动器用于实际起飞和着陆运输机应用的必要性。这些研究结果进行了比较，在一个类似的高升力平台上使用压电驱动的零净质量流量驱动的研究。
The efficacy of a single dielectric barrier discharge plasma actuator for controlling turbulent boundary-layer separation from the deflected flap of a high-lift airfoil is investigated between Reynolds numbers of 240,000 (15 m/s) and 750,000 (45 m/s). Momentum coefficients for the dielectric barrier discharge plasma actuator are approximately an order of magnitude lower than those usually employed for such studies, yet control authority is still realized through amplification of natural vortex shedding from the flap shoulder, which promotes momentum transfer between the freestream and separated region. This increases dynamic loading on the flap and further organizes turbulent fluctuations in the wake. The measured lift enhancement is primarily due to upstream effects from increased circulation around the entire model, rather than full reattachment to the deflected flap surface. Lift enhancement via instability amplification is found to be relatively insensitive to changes in angle of attack, provided that the separation location and underlying dynamics do not change. The modulation waveform used to excite low-frequency perturbations with a high-frequency plasma-carrier signal has a considerable effect on the actuator performance. Control authority decreases with increasing Reynolds number and flap deflection, highlighting the necessity for further improvement of plasma actuators for use in realistic takeoff and landing transport aircraft applications. These findings are compared to studies on a similar high-lift platform using piezoelectric-driven zero-net-mass flux actuation.