Ultrafast X-ray tomography raw-data of bubbly two-phase pipe flow around a ring-shaped constriction

For the investigation of bubbly two-phase flow, which should serve as a future benchmark experiment for CFD code validation, an experimental study has been conducted at the <strong>T</strong>ransient Tw<strong>o-P</strong>hase <strong>Flow</strong> (TOPFLOW) facility at Helmholtz-Zentrum Dresden – Rossendorf (HZDR) using ultrafast electron beam X-ray tomography (UFXRAY). In this study, flow constrictions were installed into a pipe to create a generic three-dimensional flow field as an advanced test case for CFD codes. UFXRAY provide valueable data of the gas phase dynamics with high temporal and spatial resolution.

The provided data set contains tomography raw-data for the experimental series L30 that uses a <strong>ring shaped</strong> flow constriction with a blockage ratio of 0.5. 

For visualization, the data might be opend with Fiji. Therefore choose Import-&gt;Raw... In the following window specify "Image type" as 16-bit Unsigned, "Width" as 288 pixels and "Height" as 500 pixels for 2x1000Hz measurement or 200 pixels for 2x2500Hz measurement. Make sure that "Little-endian byte order" is checked. A data set contains image frames of both scanning planes in alternating order. Therefore, if only a single scanning plane is required, the offset and gap parameters need to be set to 288000 bytes for 2x1000Hz measurement or 115200 bytes for 2x2500Hz measurement.

为开展气泡两相流研究以作为未来计算流体动力学（Computational Fluid Dynamics，CFD）代码验证的基准实验，本研究于亥姆霍兹德累斯顿-罗森多夫研究中心（Helmholtz-Zentrum Dresden – Rossendorf，简称HZDR）的瞬态两相流（Transient Two-Phase Flow, 简称TOPFLOW）实验台架上，采用超快电子束X射线层析成像（ultrafast electron beam X-ray tomography, 简称UFXRAY）技术完成了实验测试。研究中于管道内加装流动缩狭装置，以构建通用三维流场，作为CFD代码的高级测试工况。UFXRAY可获取具备高时空分辨率的气相动力学珍贵实验数据。

本次提供的数据集对应实验序列L30，该序列采用阻塞比为0.5的环形流动缩狭装置。

若需对该数据进行可视化处理，可使用Fiji软件进行读取：依次选择Import->Raw...，在弹出的配置窗口中按如下参数设置：针对2×1000Hz的测量工况，将"Image type"设为16位无符号，"Width"设为288像素，"Height"设为500像素；针对2×2500Hz的测量工况，"Height"设为200像素。请确保勾选"Little-endian byte order"（小端字节序）选项。单个数据集包含两个扫描平面的图像帧，且二者以交替顺序排列。因此，若仅需单个扫描平面的数据，需将偏移量与间隙参数设置为：2×1000Hz工况下为288000字节，2×2500Hz工况下为115200字节。