小肋减阻的飞行试验方法、结果和分析

气动设计水平既是评价飞机先进性的重要指标之一，也是提高大型客机竞争力的关键，其主要目标包括增升与减阻两个方面。为满足工程应用实际需求，本文开发了一种可用于评估减摩阻效果的无接触式测量技术，用以测量高雷诺数下飞行试验中小肋的减阻效果。结果表明流经小肋壁后的来流机械能损失更少，且相较于光滑壁具有更小的流向摩阻及更高的流向速度。此外小肋抑制了机翼上表面的展向速度脉动，并推测其在小肋膜下游分布的展向条状强脉动区域与气流流经小肋膜所产生的流向涡有关，在此基础上小肋膜的流向减阻效果与展向速度脉动抑制有所关联。

FLIGHT TEST METHOD,RESULT AND ANALYSIS OF SMALL RIB DRAG REDUCTION

The level of aerodynamic design is not only one of the important indicators to evaluate the progressiveness of aircraft, but also the key to improve the competitiveness of large passenger aircraft. The main objectives include increasing lift and reducing drag. In order to meet the practical needs of engineering applications, this paper develops a non-contact measurement technology that can be used to evaluate and measure the drag reduction effect of small ribs in flight tests at high Reynolds number. The results show that the airflow flowing through the small rib is faster, the mechanical energy loss is less, and the flow friction of the small rib is smaller. In addition, the small rib suppresses the spanwise component velocity pulsation, and it is speculated that the spanwise strip strong pulsation area distributed downstream of the small rib is related to the flow direction vortex generated by the airflow flowing through the small rib. On this basis, the flow drag reduction effect of the small rib and the suppression of spanwise velocity pulsation can be interrelated.