1. Application of a new method for experimental validation of polydispersed DEM simulation of silo discharge
- Author
-
Zahra Mansourpour and Mohammed Ali Najafi-Sani
- Subjects
Materials science ,Information silo ,General Chemical Engineering ,Flow (psychology) ,Mixing (process engineering) ,02 engineering and technology ,Mechanics ,Function (mathematics) ,Solver ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Measure (mathematics) ,Discrete element method ,0104 chemical sciences ,Mechanics of Materials ,Silo ,0210 nano-technology - Abstract
There are numerous experimentally validated simulations for mono-dispersed systems in the literature based on discrete element method (DEM). In practice, however, most of granular systems consist of polydispersed assemblies of particles. Few studies have considered the effect of polydispersity, and yet fewer have experimentally validated the results. In this study, application of a new experimental method for granular flow analysis is presented, capable of validating the results of an in-house developed GPU-based DEM solver in both monodispersed and polydispersed assemblies. Silo discharge is chosen as the case study in which discharge time, flow pattern and more importantly, the outlet composition variation with time (for polydispersed configurations) have been experimentally evaluated and validated with numerical results. The outlet composition, which is the ratio of fine to coarse particles in the outlet stream, is an essential measure of segregation in polydispersed silos, and its numerical prediction can be correct only if the interactions between fine and coarse particles within the silo are modelled precisely. Measuring this parameter is not possible using conventional experimental methods established in silo discharge studies such as high speed photographing or high-frequency weight measurement of the bed. A new apparatus has been developed which can measure this parameter. The device is a compartmented wheel rotating with a motor which gathers the outlet stream of the silo into different compartments. Due to practical limitations, design and function of the apparatus are not ideal. Forward mixing, distribution of particles with the same resident time in different compartments, is the most critical problem. Non-idealities must be compensated by means of post-processing codes so that comparable results are obtained from experiment and simulation.
- Published
- 2020