International Society for Industrial Process Tomography

Time-lapse X-ray Tomography and Data Processing Study of Organic Granular Material Behaviour during Mass Flow in Silo

Krzysztof Grudzień¹, Selam Waktola¹, Konrad Miśkiewicz¹, Jerome Adrien²,
Eric Maire² and Laurent Babout¹

¹ Institute of Applied Computer Science, Lodz University of Technology, 18/22 Stefanowskiego st., Lodz, Poland

² MATEIS INSA Lyon, Bat B Pascal, 7 Ave Jean Capellexs, Villeurbanne, France

^*Email: kgrudzi@iis.p.lodz.pl

ABSTRACT

Mass flow, despite being used as the main approach to discharge granular material in numerous industrial branches, still reveals lack of knowledge. For instance, there is still not a clear understanding about the relationship between the type of granular material and the discharge rate. This article investigates the behaviour of one type of organic material, sorghum, which has a nearly mono dispersed isotropic shape. Flow behaviours were investigated using a new versatile silo model during time-lapse X-ray tomography experiments. This setup allows to precisely observe the flow dynamics of the granular material. Concentric flow investigation is considered in the article and the effect of wall roughness on granular packing density is investigated. This is made possible thanks to the chosen image processing method, which combines watershed-based method with the skeleton by influence zone algorithm. This proposed image processing method allows to uniquely estimate local volume fraction and its evolution during discharge. This new insight can serve as baseline for future comparison with other granular materials and with numerical simulations.

Keywords silo design, X-ray tomography, mass flow, image processing, volume fraction distribution

Industrial Application General