应用数字图象处理技术研究涡流场

本文描述的实验采用干冰为示踪粒子，对脱体涡系作了流动显示，并对摄取的图片进行了数字图象处理。结果清楚地提示了涡的三层结构。在主涡的诱导下，出现二次涡，而二次涡会影响脱体涡的速度分布。实验还得到了脱体涡流场的灰度分布图，并将得出的涡核直径与ＬＤＶ得到的结果进行了对比。实验结果还证明来流迎角、侧滑角及前缘后掠角会影响涡核的位置和强度。当机翼前缘后掠角增加时，脱体涡向不稳定方向发展。

Study on Vortex Flow Field Using Digital Image Processing Technique

An experiment of using the dry ice as the tugged particle is described,and the flow visualization of the detached vones flow is discussed on the basis of digital image processing. The results clearly present the three-dimensional structure of the vortex flow. The quadratic vortexes produced under the guide of the main vortex will affect the distribution of velocity. The grey scale distribution diagram of the detached vortex flow is obtained,and the measured diameter of the detached vortex core is compared with the results by LDV.The angle of attack of the leading,the angle of side sliding,and the sweepback angle of the coming flow will affect the position and the intensity of the vortex core. The detached vortex is developing in the instability direction as the sweepback angle increases.