Variation of Heat Flux at Lower Frequencies of Vibration in a Vibrated Granular Bed

Nadeem Ahmed Sheikh,Muzaffar Ali,Shehryar Manzoor

doi:10.1155/2015/598354

Abstract

Granular flows in vibrated bed exhibit various physical phenomena primarily driven by vibrating base. As the vibrating surface is the only source of energy in an otherwise dissipative flow, most of the theoretical models relate the steady state energy input to the RMS velocity of vibration. Here variation of heat flux is studied at varying frequency of vibration while keeping the RMS vibration velocity and the cell loading constant. Using single particle analysis and MD simulations, an extended version of grain-base collision is observed resulting in the reduction of heat flux at lower frequencies (<50 Hz) of vibration. The presented findings are important as most experimental studies are reported at these frequencies of excitation.

Highlights

Granular flows in the arrangement of a vibrated bed exhibit various behaviors primarily depending on the strength of vibration [1,2,3,4,5]
Substantial amount of work can be found on the simulation of rapid granular flows using kinetic theory models especially for dilute and nearly elastic flow nature [12, 13]
A recent study has shown that as the base time period approaches the duration for a typical grain-base collision the amount of steady state heat flux may reduce drastically [20]

Summary

Introduction

Granular flows in the arrangement of a vibrated bed exhibit various behaviors primarily depending on the strength of vibration [1,2,3,4,5]. At sufficiently higher levels of acceleration the gaseous or rapid motion of granular material is observed Such kind of flows is of greater interest from the aspect of modeling using kinetic theory models and continuum order descriptions [6, 7]. A recent study has shown that as the base time period approaches the duration for a typical grain-base collision the amount of steady state heat flux may reduce drastically [20]. This leads to breakdown of instantaneous binary collision models. Estimation of low frequency influence on the amount of heat flux imparted in the bed is important

System Description

Conclusion