为降低来流阵风引起的飞机气动载荷，基于CFD数值模拟对自然层流翼型NLF416开展了后缘喷流作用减缓阵风载荷的研究，研究包括开/闭环控制两部分工作，分别分析喷流动量系数、延迟时间及反馈系数和变量等对控制效果的影响。结果表明：喷流作用对阵风减缓是有效的，合适的喷流动量系数可有效减缓阵风引起的升力响应，降低响应变化量约78.9%，考虑喷流的迟滞效应后，可进一步减小10%左右；闭环控制方面，相比基于升力系数反馈存在的各种问题，基于上游阵风速度的控制明显较优，不仅有效降低了升力峰值，多减小了响应变化量约14.3%，动量系数也类似余弦函数变化，其控制效果更接近于开环控制。将这一结果运用至多种形式的连续阵风响应抑制中，也得到了较好的减载效果，进一步验证了喷流控制适用的广泛性。
Gust load alleviation by trailing edge blowing is studied based on CFD numerical simulation for natural laminar airfoil NLF416, involving two sections:open and closed loop control. The effects of the momentum coefficient, time-lag, feedback factor and variable on the control effects are analyzed, and the results indicate the feasibility of gust load reduction by jets, and that the variation of lift response in the gust flow can decrease by about 78.9% with an accurate momentum coefficient. The response variation can be further reduced by 10% in consideration of the time-lag. For the closed-loop control, the feedback based on the gust velocity upstream is better than that based on the lift coefficient. The former can reduce both the lift peak and the response variation by 14.3% compared with the latter, and keep the change in the momentum coefficient similar to the cosine function. The results of feedback based on the gust velocity are close to those of the open-loop control. The control system is applied to the suppression of other continuous gust responses to verify the universality of jet flow control, and the results indicate a significant load reduction.
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