Development of a Multiphase "3-D+" Boundary-Layer Flow Visualization Technique

9713857 J.Hoyt开发了一种适用于湍流显示的流动示踪剂，并由P.I.对二维流进行了测试。示踪剂由剪切增稠和高拉伸粘度流体组成，当流动变得湍流时不会像以前使用的示踪剂那样扩散。提出了将可视化方法推广到三维流动，并将其应用于湍流边界层中的相干结构。新的方法提供了同时观察三个方向的流动(称为3D+)，这使得能够更容易地识别投影在三个不同平面上的流动结构(侧面、顶部和流动方向的正面)。关于“马蹄形”涡和大型有序结构的初步结果是非常有希望的。实验工作将与布里斯托尔大学的R.H.J.塞林教授合作进行，那里准备了实验设备。该方法有望为理解和模拟包括剪切流和尾迹流在内的空间湍流结构提供新的见解。还设想将该技术应用于其他复杂的流动，如弥散流动、泥沙输送、透平机械，以及用于教育目的。***

Abstract 9713857 J. Hoyt A flow tracer suitable for turbulent flow visualization has been developed and tested by the P.I. for two-dimensional flows. The tracer, composed of shear-thickening and high extensional viscosity fluids, does not diffuse when the flow becomes turbulent like the previously used tracers do. The extension of the visualization method to three-dimensional flows, with application to coherent structures in turbulent boundary layer, is proposed. The new approach provides simultaneous viewing the flow three directions (called 3-D+), that allows for easier identification of the flow structures as projected on three different planes (side, top, and frontal to the flow direction). The preliminary results on "horseshoe" vortices and large organized structures are very promising. The experimental work will be performed in collaboration with Prof. R.H.J. Sellin of the University of Bristol, where experimental facilities are prepared. The method is expected to provide new insights into understanding and modeling of the spatial turbulent structures, including shear flows and wake flows. The application of the technique to other complex flow, such as dispersion flows, sediment transport, turbomachinery, and for educational purposes also is envisaged. ***