Zbigniew Chaniecki

ECT Image Analysis Methods for Shear Zone Measurements during Silo Discharging Process

Abstract The paper covers the electrical capacitance tomography (ECT) data analysis on shear zones formed during silo discharging process. This is due to the ECT aptitude for detection of slight changes of material concentration. On the basis of ECT visualisations, wall-adjacent shear zone profiles are analysed for different wall roughness parameters. The analysis on changes of material concentration, based on ECT images, enables the calculation for the characteristic parameters of shear zones—size and material concentration inside the shear zone in a dynamic process of silo discharging. In order to verify the methodology a series of experiments on gravitational flow of bulk solids under various conditions were conducted with different initial granular material packing densities and silo wall roughness. The investigation shows that the increase in container wall roughness is an effective method for reducing the dynamic effects during the material discharging, since these effects are resulted from the resonance between hopper construction and trembling material. Such effects will damage industrial equipment in practical applications and need further investigation.

Visualisation of Granular Material Concentration Changes, During Silo Discharging Process, Using ECT Large Scale Sensor

Abstract Measuring changes of bulk materials concentration during gravitational flow, a silo emptying is essential information for the assessment of the behaviour and condition of the material during the emptying of the silo. Parameters obtained during this process are important both in terms of process economics and safety, are the basis for monitoring and diagnostics of the process. Affect the current process, but primarily are the result of their filling the silo, and the process of storing the material. Previous studies, conducted by a team of authors, the laboratory-scale silos and numerical calculations and simulations of its increase, helped build the ECT sensor on a large scale. Results related to the change of scale of the sensor and the actual measurements will be discussed in the article. Proposed by the authors of the paper, the method of visualization, performed in the measuring process, helps to ask about the process and suggests a methodology for dealing with the material stored in the silo.

Diagnostic System of Gravitational Solid Flow Based on Weight and Accelerometer Signal Analysis Using Wireless Data Transmission Technology

Abstract The paper presents results of the scale-up silo flow investigation in based on accelerometer signal analysis and Wi-Fi transmission, performed in distributed laboratory environment. Prepared, by the authors, a set of 8 accelerometers allows to measure a three-dimensional acceleration vector. The accelerometers were located outside silo, on its perimeter. The accelerometers signal changes allowed to analyze dynamic behavior of solid (vibrations/pulsations) at silo wall during discharging process. These dynamic effects are caused by stick-slip friction between the wall and the granular material. Information about the material pulsations and vibrations is crucial for monitoring the interaction between silo construction and particle during flow. Additionally such spatial position of accelerometers sensor allowed to collect information about nonsymmetrical flow inside silo.

Educational presentation of raw data in electrical capacitance tomography

In this paper the software for visualisation of dense-phase pneumatic flow is presented. The main information about Electrical Capacitance Tomography (ECT) was introduced. Methods of tomograph data analysis have been discussed. It has been pointed out that the analysis of raw data is more efficient than that of reconstructed data. It is considered how student can examine data, using this program, to learn about process and measurements.