Development of 3-dimensional PTV with prismatic light sheet

棱镜光片3维PTV的开发

• 批准号: 13650213
• 负责人: MOCHIZUKI Takaaki
• 金额: $ 0.77万
• 依托单位: Tokyo Gakugei University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13650213/
• 关键词: 3-dimensional particle tracking; 3-D PIV; 3-D PTV; Prismatic light sheet; 3-dimensional flow visualization; Color image analysis; Particle tracking velocimetry; Color imaging; Visualization technique

When rigid particles pass through a light sheet whose spectrum varies with its thickness, they reflect rays of varying colors. If we observe the particles using a color video camera whose axis is set normal to the light sheet, their motions can be determined from their loci and colors, as observed on a video monitor. Based on this principle, we have developed a novel scheme to determine the 3-dimensional translational motions of rigid particles in a liquid medium using only one color video camera. The rays reflected from particles are related to their loci through color analysis. In this study, we developed two types of illumination system to make the light sheet noted above, and we studied a calibration scheme by which we could obtain a relation between loci of the particles and rays reflected by the particles. Using the calibration curve obtained using the scheme shown in this study, we estimated the loci of particles with a diameter of about 0.1 mm ; the maximum error was 0.51 mm, and the standard deviation of the calibration curve was 0.21 mm when the hue angle was between 0.9 degree and 110 degree. An effect of concentrations of the particles in the liquid medium on the measuring accuracy for determining loci of the particles, and an effect of size distribution of the particles on the accuracy were also studied experimentally. We also studied the way in which loci and rays of the particles recorded in an image by the color video camera were detected through automatic image analysis by a computer.

当刚性粒子穿过光谱随厚度变化的光片时，它们反射不同颜色的光线。如果我们用彩色摄像机观察粒子，摄像机的轴垂直于光片，它们的运动可以从它们的轨迹和颜色确定，就像在视频监视器上观察到的那样。基于这一原理，我们提出了一种只用一台彩色摄像机测定液体介质中刚性粒子三维平移运动的新方案。通过颜色分析，从粒子反射的光线与它们的轨迹有关。在这项研究中，我们开发了两种类型的照明系统，使上述光片，我们研究了校准方案，通过该方案，我们可以获得粒子的轨迹和粒子反射的光线之间的关系。使用本研究所示方案获得的校准曲线，我们估计了直径约为0.1 mm的颗粒的轨迹;当色调角在0.9度和110度之间时，最大误差为0.51 mm，校准曲线的标准偏差为0.21 mm。还通过实验研究了液体介质中的颗粒浓度对确定颗粒轨迹的测量精度的影响，以及颗粒的尺寸分布对精度的影响。我们还研究了如何通过计算机自动图像分析检测彩色摄像机记录在图像中的粒子的轨迹和射线。