Measurement of solid concentration changes at funnel flow silo using X-ray tomography

Krzysztof Grudzie?1, Maciej Niedostatkiewicz2, Eric Maire3, Andrzej Romanowski1, Dominik Sankowski1, Zbigniew Chaniecki1

1Technical University of Lodz, Computer Engineering Department, Lodz, Poland, kgrudzi@kis.p.lodz.pl 2Gdansk University of Technology, Department of Fundamentals of Building and Material Engineering, Gdansk, Poland

3 Université de Lyon, INSA-Lyon, MATEIS CNRS, Villeurbanne, France

ABSTRACT

Silos, e.g. containers for storing and loading bulk solids, can cause many problems during normal work. This can be an effect of construction design imperfections and flow of the bulk solid instabilities. Problems with silo discharging may be a result of material or unsuitable outlet adjustment. Therefore Knowledge of the distribution of the concentration of the bulk solid above the outlet can be crucial to for silo improved design and operation. Therefore, application of the non-invasive measurement methods is necessary to explore volumetric behaviour of material concentration changes during silo flow.

The paper presents results of solid concentration changes observation at the funnel flow silo. Experiments were preformed with application of the X-ray tomography. Tests in model silo were carried out with different initial densities of sand and silo wall roughness. The change of the width of the core of flow, time of silo emptying and changes of the concentration at the stagnant zone were discussed. Results were presented in form of 3D reconstruction, 2D images and 1D continuous plots.

Keywords granular material, X-ray tomography, silo flow, continuous radiation, solid concentration