空气动力学学报
空氣動力學學報
공기동역학학보
ACTA AERODYNAMICA SINICA
2015年
3期
367-374,405
,共9页
地面效应%翼尖涡%PIV%波浪地面%拖曳水槽%实验研究
地麵效應%翼尖渦%PIV%波浪地麵%拖抴水槽%實驗研究
지면효응%익첨와%PIV%파랑지면%타예수조%실험연구
wing in ground effect%tip vortices%PIV%sine wavy surface%towing tank%experi-mental study
完成了 NACA23012机翼地面效应条件下翼尖涡结构及升阻力特性实验。实验在拖曳水槽中模拟机翼的飞行状态，获得了在多种飞行高度、0°攻角时机翼在水平地面和正弦波浪地面附近的升／阻力、翼尖涡流场的变化规律，对比分析了水平地面和波浪地面附近翼尖涡速度、涡量分布的区别及其可能对机翼升／阻力造成的影响。实验结果表明：即使在正弦波浪地面附近，随着机翼逐渐靠近地面，升力逐渐减小至负升力，翼尖涡的强度亦发生相应变化；尤其是在小间隙比、负升力情况下，翼尖涡的旋转方向产生了改变；流场结构不仅受机翼距地面高度影响，也随着波浪地面与机翼瞬时所处位置构成的相对相位关系的不同而变化，并且涡量沿波浪地面运动的变化呈现周期性，但变化规律并不符合正弦周期，主要原因在于波浪地形与下翼面所构成的流道形状及狭窄程度的周期性变化对翼尖涡流场结构的发展和演化产生不同程度的抑制。
完成瞭 NACA23012機翼地麵效應條件下翼尖渦結構及升阻力特性實驗。實驗在拖抴水槽中模擬機翼的飛行狀態，穫得瞭在多種飛行高度、0°攻角時機翼在水平地麵和正絃波浪地麵附近的升／阻力、翼尖渦流場的變化規律，對比分析瞭水平地麵和波浪地麵附近翼尖渦速度、渦量分佈的區彆及其可能對機翼升／阻力造成的影響。實驗結果錶明：即使在正絃波浪地麵附近，隨著機翼逐漸靠近地麵，升力逐漸減小至負升力，翼尖渦的彊度亦髮生相應變化；尤其是在小間隙比、負升力情況下，翼尖渦的鏇轉方嚮產生瞭改變；流場結構不僅受機翼距地麵高度影響，也隨著波浪地麵與機翼瞬時所處位置構成的相對相位關繫的不同而變化，併且渦量沿波浪地麵運動的變化呈現週期性，但變化規律併不符閤正絃週期，主要原因在于波浪地形與下翼麵所構成的流道形狀及狹窄程度的週期性變化對翼尖渦流場結構的髮展和縯化產生不同程度的抑製。
완성료 NACA23012궤익지면효응조건하익첨와결구급승조력특성실험。실험재타예수조중모의궤익적비행상태，획득료재다충비행고도、0°공각시궤익재수평지면화정현파랑지면부근적승／조력、익첨와류장적변화규률，대비분석료수평지면화파랑지면부근익첨와속도、와량분포적구별급기가능대궤익승／조력조성적영향。실험결과표명：즉사재정현파랑지면부근，수착궤익축점고근지면，승력축점감소지부승력，익첨와적강도역발생상응변화；우기시재소간극비、부승력정황하，익첨와적선전방향산생료개변；류장결구불부수궤익거지면고도영향，야수착파랑지면여궤익순시소처위치구성적상대상위관계적불동이변화，병차와량연파랑지면운동적변화정현주기성，단변화규률병불부합정현주기，주요원인재우파랑지형여하익면소구성적류도형상급협착정도적주기성변화대익첨와류장결구적발전화연화산생불동정도적억제。
An experimental study on the tip vortices and lift/drag forces of a NACA23012 wing in adjacent to the flat and the sine wavy surface at zero angle of attack is introduced.The experiment is conducted in a towing tank.The study focuses on the hydrodynamics and evolution of the tip vortices of the wing close to the flat and the sine wavy surface with different ground height,velocity and vorticity distribution,as well as their influence on the lift/drag force of the wing are compared.The results show that,the lift force decreases from positive to negative as the wing gets closer to the wavy surface,the intensity of the tip vortices change as well,and the shape of tip vorticesis is deformed correspondingly.Especially,for the case of small ground height and negative lift force,the rotation direction of the tip vortices is changed.The flow struc-ture is not only affected by the wing ground height,but also influenced by the phase relation of the wing and the ground,i.e.the instantaneous shape of the flow channel between the lower sur-face of the wing and the wavy ground surface.And the vorticity of the tip vortices along the wavy surface presents some periodic variation,whereas the variation does not comply with sine regular-ity.The reason is that the periodical variation of the shape of the flow channel and the stenosis degree of the channel beneath the wing brings a different level of inhabitation to the evolution of the tip vortices.
