Effects of vibrator characteristics on uncloging and outflow of silo containing granular material-DEM approach

Document Type : Original Article

Authors
Akbar Jafari 1
Ali Abolghandi 2
Arash Gharibi 2
1 Department of Mechanical Engineering, Technical and Vocational University(TVU), Tehran, Iran.
2 Faculty of Mechanical Engineering, Sirjan University of Technology, Sirjan, Iran.
10.22034/stme.2022.162700
Abstract
The output flow regime of the silo is influenced by different variables including its geometrical features, type and size of particles and flow aid devices. In this research, the Discrete Element Method (DEM) has been used to simulate and study effects of vibration, caused by installing a vibrator, on the output flow of silos containing granular materials. In order to ensure the accuracy of the simulations, the sensitivity analysis was performed on the numerical solution factors. For validation, comparisons with experimental and numerical results available in the open literature have been made. Observing the real conditions shows that when the opening of the silo is not large enough, the silo becomes blocked. Here, by performing a number of simulations, the opening size threshold at which the silo becomes blocked was determined and named as the critical size. Sizes larger and smaller than that threshold were introduced as non-critical and super-critical respectively, and numerical studies were carried out on these three cases. Numerical studies have been done for different values of the vibration frequency and amplitude. Moreover, to find out effects of the vibrator location, relevant stimulations were conducted, and based on the obtained results, when its location was within 20% of the bottom height of the discharge funnel, it had the greatest effect. As another conclusion, it was found that by increasing the vibration frequency, the impact of the vibrator increases however, the difference in the effects of different frequencies decreases with the increase of the vibration amplitude. Regarding effects of the studied variables, in addition to the theoretical explanation, their physical interpretation and reasoning has also been discussed.
Keywords
Silo
Blockage
granular material
DEM
Subjects
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Science and Technology in Mechanical Engineering
Volume 1, Issue 1 - Serial Number 1
February 2023
Pages 39-57

  • Receive Date 21 August 2022
  • Revise Date 05 October 2022
  • Accept Date 11 December 2022
  • First Publish Date 11 December 2022
  • Publish Date 20 February 2023