后退式微型后缘装置对翼型气动特性影响的实验研究

The experimental investigation on the effect of rearward Mini-TED to the aerodynamic characteristics of an airfoil

介绍了装有后退式微型后缘装置(Rearward Mini-TED)的NACA23012翼型在低雷诺数条件下的表面压力分布、气动力和PIV速度场的风洞实验结果,并与NACA23012原型翼的对应测量结果进行了对比分析,以探讨Mini-TED装置对翼型流场、气动特性产生的影响。本实验风速为15m/s,以弦长为特征量的雷诺数为Re≈1.3×105,翼型表面压力分布采用测压孔和压力传感器测量,通过积分获得翼型升力和压差阻力,并利用尾耙测量翼型受到的总阻力。结果表明,后退式Mini-TED翼型改变了翼型周围的流场速度分布和尾流流动结构,导致上翼面吸力和下翼面的压力升高,使翼型升力增加,但压差阻力也增加。同时发现后退式Mini-TED翼型使前驻点位置后移,加快了上翼面的流动速度,后缘分离受到抑制。

The pressure distribution, aerodynamics and PIV velocity fields of a NACA23012 airfoil mounted with a rearward Mini-TED captured in a low speed wind tunnel tests are introduced and compared with experimental results of a NACA23012 prototype airfoil in this paper, in order to investigate the influence of the Mini-TED to the flow field and aerodynamics loads of the airfoil. The Reynolds number is 1.3 × 10^5 based upon the chord length of the airfoil. The pressure distribution on the airfoil is measured using the pressure tubes and pressure transducers, and then the results are integrated to obtain the lift force and pressure drag acting on the airfoil. The total drag is measured using the comb of stagnation pressure based on the momentum theorem. The velocity fields around the airfoil are captured by a PIV system. The rearward Mini-TED in- duces changes to the flow velocity around the airfoil and the wake flow structure, which leads to the variation of the pressure distribution on the suction and pressure surfaces and the increase of both the lift and pressure drag. The position of the front stagnation point of the airfoil with a Mini-TED shifts downstream slightly compared with that of the NACA23012 prototype airfoil, which consequently leads to the increase of the flow velocity on the suction surface and the suppression of the flow separation near the trailing edge.