涡切片图象立体重建

 <正> 1.引言 激光片光技术和流体中微粒的光散射效率逐步提高;从烟雾、水汽到激发诱导荧光使流动可视化程度不断开拓。许多研究工作需要通过观察切片照片获得对复杂流动整体结构的理解。因此,将系列二维切片照片重建成立体图象是十分有意义的。 近年来这方面比较典型的工作有Jimener的平面混合层和Agui and Hesselink的共轴喷流重建,分别在平面型和封闭柱面型的不同气流混合界面研究涡系的生成和发展。用涡迹切片重建的三维图象能清楚地显示涡的内部结构,对提供合理的流动假说和计算模型有重要意义。

THE DIMENSIONAL RECONSTRUCTION OF VORTEX CROSS-SECTION IMAGES

The problems of 3-D vortex reconstruction by means of vortex cross-section visualization obtained with a laser sheet is discussed. It includes the cross-section sampling methods, digital image processing, 3-D display and reconstruction algorithms. A 3-D representation of the vortex field is obtained by stacking the contours in sequence with a constant separation distance between cross-sectional planes.The topological features of the spatial construction of vortex can be comprehended from this display of perspective projections. The multiple directional 3-D staircase surface vortex representations are given and the experimental model is a delta wing with flap in transonic wind tunnel.