As Discrete Element Modelling (DEM) increases its utilization as tool for the simulation of particulate materials in a variety of processing unit operations, there is a continuous focus on develop robust methodologies for model calibration to guarantee reliable predictive results. This paper focus on providing insights on advantages and limitations on typical approaches for calibration and validation. The calibration process using a series of small scale tests was then validated experimentally and numerically utilizing independent application tests.
The preparation of nano/micromotor systems has been a hot topic in nanotechnology and biotechnology for the last decade. This review explains the underlying physics of the nano/micromotors, which is completely different from that of conventional macroscale motors. Additionally, the authors introduce various types of nano/micromotors, especially chemical reaction propelled motors.
Widely used in the minerals, cement, ceramics and chemical industries for 150 years, ball mills have attracted the attention of engineers in describing size reduction quantitatively for over 70 years. However, this last quarter of a century has been particularly active, given the widespread use of the discrete element method, which has triggered the development of novel modeling approaches to describe size reduction in them. The work reviews the various hurdles that have been faced by researchers and the solutions proposed to overcome them in describing size reduction in ball mills using the so-called advanced models, with emphasis on the work by the author and his co-workers at the University of Rio de Janeiro.
The present study address the challenges with modeling the fluidization of ground biological materials which are typically non-spherical in shape, and have widely varying sizes. The Ergun equation that is commonly used to model particle fluidization was modified to incorporate non-uniformity sizes, shape factor, and the high void ratio that are typically present in ground biological materials. The results of the study will address the challenges in using models to scale up, size, and design equipment reactors for fluidizing biomass and other biological materials.
Novel concepts for solar cells to increase the energy conversion efficiency have proven very promising over the last decade or so. However, implementation of such light management designs have not reached commercial products. Bottom up fabrication with nanoparticles, especially from gas aggregation nanoparticle source, are the most likely path to industrial realisation. In this review paper we present a wide range of possibilities to use such nanoparticles to increase the efficiency of solar cells, both as light management and constituent.
Mixing and Segregation in Powders: Evaluation, Mechanisms and Processes
Released: March 29, 2014 | Volume 27 Pages 3-17