Executive Summary
During the first year of this project, a postdoctoral research was hired with background in DEM and started in January of 2013. One student was working on subjects that are close to this project. A second student was added in summer. A parallel project with Abbvie focuses on the modeling of compaction and strength of single type particles and leverages the effort of this project. In summary the following activities were undertaken:
A literature survey was performed to identify prior efforts on DEM for powder compaction
A careful study was conducted to identify potential obstacles for the application of DEM on powder compaction
LIGGGHTS, an open source, highly parallelized code for granular phenomena was installed and used extensively.
A preliminary model that takes into account contact interactions was implemented in LIGGGHTS and appears to perform better than prior efforts (Storakers model). Results from this work are being analyzed.
Preliminary results for the compaction of two phase mixture were obtained by using the Storakers model. Despite its lack of accuracy, this work provides interesting insights in the problem in terms of relative magnitude of interparticle forces on different types of contacts.
Ongoing work focuses on finalizing the selection of force-displacement model for high densities, introduction of different size and different properties effect in it and their cross interaction. Our work has also shown ,there may be a need to introduce an elastic component in the force-displacement response , in order to understand some of the aspects of mechanical behavior of compacted powder mixtures.