Authors: Rohan Panchadhar Keith A Gonthier
Publish Date: 2009/07/02
Volume: 44, Issue: 5, Pages: 717-744
Abstract
A combined finite and discrete element method is used to examine the energetics of a twodimensional microparticle cluster that impacts a rigid planar wall The method combines conservation principles with an elasticviscoplastic and friction constitutive theory to predict thermomechanical fields within particles resulting from both particlewall and particleparticle contact Emphasis is placed on characterizing the temporal and spatial partitioning of cluster energy with impact angle 0◦ ≤ phi ≤ 80◦ where phi = 0◦ corresponds to normal impact Predictions for a closepacked cluster of wellresolved particles having an average initial radius and uniform speed of 50μm and 300 m/s indicate that particles adjacent to the wall experience the largest plastic and friction work Friction significantly affects cluster kinetic energy but minimally affects its elastic strain energy and plastic work Local temperature rises in excess of 900K are predicted for phi = 0◦ increasing to 4400K for approximately phi 60◦ with most of the cluster mass ≈98 experiencing temperature rises less than 200K due to plastic work These predictions highlight the importance of friction work as a heating mechanism that may induce combustion of energetic clusters Sensitivity of the cluster response to its initial packing configuration is demonstrated
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