Contact parameter estimation for DEM simulation of iron ore pellet handling

Abstract The appropriate choice of contact parameters is of great importance, particularly when simulations using the discrete element method (DEM) are run with the aim of capturing quantitative information on collision events that occur among the individual particles, as what happens during handling of iron ore pellets. The paper analyzes the use of tests conducted with single pellets for estimating material and contact parameters that are required in DEM simulations using the no-slip Hertz–Mindlin model. Tests included impact load cell, tribometer, drop tests and a simple test in which the rolling angle of individual pellets is measured. It is concluded that, provided particle shapes are described appropriately, DEM simulations provide reasonably realistic predictions of pellet motion in assemblies from contact parameters measured on the basis of single-particle tests. In this case the physical significance of the contact parameters is maintained. However, if pellets are described in a simplistic way as spheres, then the DEM simulation of their flow no longer matches the experimental results, requiring fitting some of the contact parameters in order to match the observed global flow, so that much of the physical meaning of the parameters is lost.

[1]  Luís Marcelo Tavares,et al.  Modeling ore degradation during handling using continuum damage mechanics , 2011 .

[2]  Luís Marcelo Tavares,et al.  Comparison of natural and manufactured fine aggregates in cement mortars , 2007 .

[3]  Paul W. Cleary,et al.  Comparison of DEM and experiment for a scale model SAG mill , 2003 .

[4]  L. M. Tavares,et al.  Single-particle fracture under impact loading , 1998 .

[5]  Paul W. Cleary,et al.  Predicting charge motion, power draw, segregation and wear in ball mills using discrete element methods , 1998 .

[6]  C. J. Coetzee,et al.  Calibration of discrete element parameters and the modelling of silo discharge and bucket filling , 2009 .

[7]  H. Gerçek,et al.  Poisson's ratio values for rocks , 2007 .

[8]  Harald Kruggel-Emden,et al.  Comparison of the multi-sphere and polyhedral approach to simulate non-spherical particles within the discrete element method: Influence on temporal force evolution for multiple contacts , 2011 .

[9]  Paul W. Cleary,et al.  An investigation of the comparative behaviour of alternative contact force models during elastic collisions , 2011 .

[10]  Malcolm Powell,et al.  Power draw estimations in experimental tumbling mills using PEPT , 2011 .

[11]  Peter W Wypych,et al.  Investigation into calibration of discrete element model parameters for scale-up and validation of particle–structure interactions under impact conditions , 2011 .

[12]  W. Ketterhagen,et al.  Modeling the motion and orientation of various pharmaceutical tablet shapes in a film coating pan using DEM. , 2011, International journal of pharmaceutics.

[13]  Arno Kwade,et al.  Experimental investigations and modelling of the ball motion in planetary ball mills , 2011 .

[14]  Wei Ge,et al.  Simple measurement of restitution coefficient of irregular particles , 2004 .

[15]  Paul W. Cleary,et al.  DEM prediction of industrial and geophysical particle flows , 2010 .

[16]  Runyu Yang,et al.  Discrete particle simulation of particulate systems: A review of major applications and findings , 2008 .

[17]  Michael H. Moys,et al.  Assessment of discrete element method for one ball bouncing in a grinding mill , 2002 .

[18]  Brahmeshwar Mishra,et al.  On the determination of contact parameters for realistic DEM simulations of ball mills , 2001 .

[19]  Runyu Yang,et al.  Effects of disc rotation speed and media loading on particle flow and grinding performance in a horizontal stirred mill , 2010 .