摘要
突然启动流动问题在气动弹性、扑翼飞行和机动飞行中有重要应用价值。鉴于此,对突然启动流动问题涉及的流动与升力演化机制和理论分析方法进行统一介绍并指出目前的理论空白。比较性地介绍了升力随时间变化的原因、预测升力演化的理论方法和主要变化规律。从中发现,不可压缩和可压缩突然启动问题存在各自独立的研究方法与结论,因此进行统一介绍与分析对建立二者之间的关联有指导意义。同时指出,大迎角可压缩突然启动问题尚无理论分析方法和研究结果。作为一项补充研究,采用数值计算发现一个之前尚未报道的现象,即升力系数首先从较低值快速增加至一个峰值,接着快速下降,趋于定常值。该文综述介绍的方法可用于分析突然启动问题升力演化规律。
Impulsively starting flow has important applications in aero-elastics, flapping flight and flight maneuvering. In this paper we provide a state-of-art overview of the related flow characteristics, lift evolution mechanisms and analytical methods for starting flow and point out new issues for future studies. It is shown that starting flow problems have been treated sepa- rately to have independent methods and conclusions and the present survey gives a link between these two apparently unre- lated problems. We point out that it lacks theoretical method and analysis for compressible starting flow at large angle of at- tack. As a supplementary study, we perform numerical computation of a hypersonic starting flow at high angle of attack and find a phenomenon never reported before: the lift increases from a small value to a high peak in a very short time and then drops to the steady state value also in a very short time. The methods provided in this review may be useful for studying the lift evolution of starting flow.
出处
《航空学报》
EI
CAS
CSCD
北大核心
2015年第8期2588-2600,共13页
Acta Aeronautica et Astronautica Sinica
基金
国家自然科学基金(11472157)
国家"973"计划(2012CB720205)~~