The role of initial horizontal position of intruder on Brazil Nut Effect phenomenon Muhammad Iqbal Rahmadhan Putra (*), Putri Mustika Widartiningsih, Dimas Praja Purwa Aji, Aufa Rudiawan, Sparisoma Viridi
Granular Physics and Fluids Laboratory
Nuclear Physics and Biophysics Research Division
Faculty of Mathematics and Natural Sciences
Institut Teknologi Bandung
Jalan Ganesha 10, Bandung 40132, Indonesia
*miqbalrp[at]gmail.com
Abstract
Brazil Nut Effect (BNE) is known as behavior when a large particle named intruder immersed in a group of smaller particles rises due to vertical vibration. Since this phenomenon has been adopted to investigate granular segregation in industries and also in particular fields like the size sorting of particles in asteroids, a complete understanding of the various parameters that affect this phenomenon is important to know. Past studies have shown that the physical properties of particles and properties of vibration play a major role in the BNE. Technically, the initial configuration of intruder and bed particles can affect the circulation of particles under vibration. However, studies on the initial position of an intruder are still lacking. In this study, we investigate how the evolution of the intruder in the segregation process by varying the initial position of the intruder horizontally which represents the initial configuration of the system as a whole. In order to be able to replicate the initial conditions for various grain and vibration parameters, we used 2-d frictionless simulations based on molecular dynamics. The three initial horizontal positions of the intruder used are (a) the middle, (b) between the middle and the edge, and (b) the edge of the container. While the variation to the frequency produces normalize acceleration \(\Gamma\) : 0.217, 0.870, 1.957, and 3.480. The result shows that the largest percentage of intruders that reach the top of the system in the final condition is the initial condition (b) with 13% followed by the initial condition (a) with 10%, while the initial condition (c) is significantly different resulting in a small percentage of 2%. The same result was observed in the three initial conditions in which no intruder was found that could rise to the top of the system with \(\Gamma\) = 0.217. In conclusion, it can be explained the role of the initial conditions of the system also still depends on the properties of vibration.
Keywords: Granular, Molecular Dynamics, Simulation, Brazil Nut Effect
