(261c) Tomographic Approach to Granular Gravitational Flow Dynamics Analysis

This paper presents capabilities of application of tomography to hopper flow dynamics analysis. We are using Electrical Capacitance Tomography (ECT) as an instrument for non-invasive in-situ visualisation and measurement. This type of process tomography modality allows study of non-conducting media such as particulate systems or powders. The results presented here are obtained with use of single plane sensor coupled with commercially available tomographic data acquisition device. The work covers the variety of tomographic data analysis methods in order to indicate their helpfulness for different purposes when analysing solid/air mixture flow. In contrast to usually deployed visualisation techniques there are also presented image post-processing methods as well as raw measurement data manipulation and some advanced statistical modelling. The purpose of this paper is to show the possibilities of ECT application to exploring the behaviour of particulates flow during hopper discharge. Hopper flow investigation can lead to improved understanding of the nature of this process and may result in significant benefits arising from better design of containers for storing and loading solid materials. Moreover, monitoring and control of the discharging solids flow structures in hoppers can be beneficial for both operation of such containers, as well, as for the better operation of industrial installations where they are used. Research and experiments presented here proven the usefulness of ECT application to dynamic processes investigation. The advanced statistical data analysis methodology and determination of spatial and temporal relationships existing in the investigating phenomena allows detection of important events, such as container blockage, even without high spatial resolution of image reconstruction.