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The numerical investigation of tensile strength of coal model on the performance of coal plow using Particle Flow Code

  • Fu, Jinwei (School of Civil Engineering and Transportation, North China University of Water Resources and Electric Power) ;
  • Haeri, Hadi (School of Civil Engineering and Transportation, North China University of Water Resources and Electric Power) ;
  • Sarfarazi, Vahab (Department of Mining Engineering, Hamedan University of Technology) ;
  • Marji, Mohammad Fatehi (Mine Exploitation Engineering Department, Faculty of Mining and Metallurgy, Institution of Engineering) ;
  • Li, Tong (School of Civil Engineering and Transportation, North China University of Water Resources and Electric Power)
  • Received : 2021.11.21
  • Accepted : 2022.03.19
  • Published : 2022.06.25

Abstract

Effects of coal tensile strength and plow configuration on the coal fragmentation process was modeled by two-dimensional particles flow code (PFC2D). Three tensile strength values, 0.5, 1,5 and 3.5 MPa were considered in this numerical study. The cutters of plow penetrated in the coal for 4 mm at a rate of 0.016 m/s. According to the PFC manual, the local damping factor was 0.7. Three failure mechanism of coal during the fragmentation process by plow were modelled. The coal material beneath the cutters showed the elastic, plastic and fracturing behaviors in this analysis. In all the models, the plastic zone was fractured and some micro-cracks were induced but the elastic zone remained undamaged. It was observed that the tensile strength affected the failure mechanism of coal significantly and as it increased the extent of the fractured zone underneath the plow cutter decreased during the fragmentation process.

Keywords

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