Time-resolved X-ray tomography of a fluidized bed

This paper discusses first results of bubbles moving through a fluidized bed imaged with an X-ray Tomographic Scanner. The scanner is made of 3 medical X-ray sources equipped with 30 CdWO4 detectors each. The fluidized bed has a diameter of 23 cm and is filled with Geldart B powder. The scanner measures the attenuation in a thin slice perpendicular to the column axis at a sampling frequency of 2500 Hz.The data collected during 2 s are reconstructed using the SART algorithm with a one-step-late correction. The reconstructions show the distribution of the bubbles in the 2-dimensional cross-section. By stacking these images, a 3-dimensional view of the bubbles in the column is represented.

Graphical AbstractA three source X-ray tomographic scanner is used to study the motion of bubbles in a 23 cm diameter fluidized bed. From the data we reconstruct the bubble distribution in a thin slice through the bed. The bubbles passing this slice are reconstructed at a rate of 250 frames/s. Stacking of the images gives a 3D representation of the bubbles.Figure optionsDownload full-size imageDownload as PowerPoint slide