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Calibration of Selected Bulk Biomaterials Parameters for DEM Simulation of Comminution Process. Case Study: Corn and Rice Grains

Kruszelnicka Weronika, Diviš Jan, Hlosta Jakub, Gierz Łukasz, Žurovec David

Advances in Science and Technology. Research Journal

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2022

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Vol. 16, no 5

64--77

EN

Computer simulation of bulk materials behavior, including comminution and fragmentation, using DEM has been growing fast, recently. One of the important tasks to get the reliable simulation results is to provide proper materials and contact parameters, which need to be determined in a series of laboratory experiments. For comminution simulation the additional parameters describing the breakage probability and breakage functions are necessary. While some simulation parameters are available in the literature for brittle materials, valid data are lacking for biomaterials such as cereal, rice or corn grains, especially for comminution parameters. The aim of this study was to present the calibration approach and determination of materials, contact, interaction and breakage parameters for grainy biomaterials. The calibration process was done for rice and corn grains. The calibration approach consists of grains size distribution and shape characterization, friction and restitution coefficient determination, and breakage probability description. Based on the results of the experiments, the models were created in the DEM software. The result was the set of calibrated parameters for rice and corn grains.

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Simulation of material flow through a sample divider

Rozbroj Jiri, Necas Jan, Zurovec David, Hlosta Jakub, Gelnar Daniel, Zegzulka Jiri

Advances in Science and Technology. Research Journal

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2018

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Vol. 12, no 1

194--199

EN

The prerequisite for a modern approach to innovative procedures of the development of current or even newly created equipment for the transport of particulate materials is the utilization of simulation methods, such as the Discrete Element Method (DEM). This article focuses on the basic, or initial, validation of movement of material through the sample divider. The mechanical-physical properties of brown coal were measured. Based on these parameters the preliminary input values for EDEM Academic were selected, and a simulation of the dividing process was run. The key monitored parameters included density and friction coefficient. Experiments on a realistic model of the equipment were performed and assessed. The total weights of brown coal at the exit from the divider were determined for a specific speed of the divider. The aim of this task was to simulate the realistically determined weight division of the brown coal sample. The result from the DEM was compared with the results of measurement on a realistic model.

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Optimization of dosing tank emptying using spiral vibration

Zurovec David, Necas Jan, Divis Jan, Hlosta Jakub, Zegzulka Jiri, Urbanova Katerina

Advances in Science and Technology. Research Journal

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2018

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Vol. 12, no 3

143--149

EN

This article addresses the optimization of a dosing tank using a spiral harmonic motion. The dosing tank is used for ashort-term storage of cohesive sand, which is then released into a tubular mold. Originally, a solution based on the principle of wiping the material using rotary blades and brushes was used to fill the molds. However, this method was not effective enough. This solution suffered from uneven dosing as well as a loss of material. The mold filling time ranged around 20 seconds. During the course of optimization of the dosing tank, a new design of the tank was created and external energy in aform of harmonic spiral vibrations was introduced into the system. The chosen shape of the harmonic spiral motion proved to be the most suitable for continuous emptying of the cohesive sand from the dosing tank into the tubular mold in a very short time. There was also a significant elimination of material losses. It was determined that the frequency of harmonic motion affects uniform dispensing of material fromtanks.