荧光微丝在低速风洞试验中应用的关键技术研究

荧光微丝法是将含有荧光物质的直径极小的丝线粘贴布置于模型表面,在紫外线照射下呈现出明显的荧光效果,以此来显示模型表面流场的试验方法,能减小丝线对流场的干扰进而更加真实地反映流场特征。基于在西北工业大学NF-3低速风洞中进行的某大型民机增升装置风洞试验,完成了低速风洞中使用荧光微丝法进行表面流动显示的关键技术研究,包括荧光微丝的制成及粘贴方式、光源的选择及拍摄技术等。模型机翼上表面丝线在不同迎角下的流谱清晰直观、区别明显、易于判读,可较为精细地反映流经翼面的气流状态和范围,并可清晰反映表面流谱随模型姿态角的连续变化情况。同一工况下与荧光油流流谱相一致,说明可较准确地显示流场。与测力试验结果的对比可以看出,荧光微丝流谱结果与测力结果相对应,可以更好地用于流场分析。

Key technologies study of fluorescent mini-tuft application in the low speed wind tunnel tests

Fluorescent mini-tuft method is a surface flow visualization technology using mini-tuft with fluorescent material to visualize the flow characteristics under the UV light of specific wavelength.This method can reduce the disturbance of the tufts to the flow and give more accu-rate flow information.In this paper,the key technologies (including the making and sticking method of the mini-tufts,choosing the wavelength of UV lights and taking photos,etc.)of fluo-rescent mini-tuft method are investigated based on a high-lift device wind tunnel test of a certain civil aircraft in NF-3 low speed wind tunnel of NWPU.The results show that,(1)the flow pat-terns at different angles of attack are clear and intuitive,and the developments of the flow states with the angle of attack are shown,(2 )the flow state and range can be easily read in detail from the flow patterns,(3)compared with the fluorescent oil flow tests,the results are relatively sim-ilar under the same experimental conditions.It shows that the fluorescent mini-tuft method can exactly display the flow field.The flow visualization results agree well with the force measure-ment experiments and thus can interpret the force measurement results.