Scaling of granular temperature in a vibrated granular bed

Abstract

Granular temperature underpins the kinetic theory of granular flows as well as models for heat transfer, segregation, erosion, attrition, and aggregation in various granular systems. It is generally thought that granular temperature in vibrated granular systems scales with the square of the peak vibrational velocity. However, careful diffusing wave spectroscopy experiments and statistical analysis of data obtained from these for a three-dimensional vibrated bed of monodisperse glass particles reveals that the granular temperature is also significantly correlated with other vibrational parameters. Reexamination of previously published data obtained by others using alternative methods further supports our thus far unremarked upon observation reported here.

Avalanche dynamics of granular materials under the slumping regime in a rotating drum as revealed by speckle visibility spectroscopy

“…Some of these are restricted to two components of motion (PIV and PTV) while the remainder can only resolve the granular dynamics to a fine scale with relatively poor temporal resolution or vice versa. In contrast, diffusing-wave spectroscopy (DWS) [22], a dynamic light-scattering (DLS) technique, is able to resolve the average of the three components of motion of grains in dense systems with spatialtemporal resolutions [23,24] that allow the probing of the microdynamics of avalanches. However, as it is based on temporal correlation functions calculated as a time average, it is not appropriate when bulk motion such as drum rotation is present.…”

CFD-PBM Coupled Simulation of Liquid-Liquid Dispersions in Spray Fluidized Bed Extractor: Comparison of Three Numerical Methods

“…(2) e drag force coefficient C D has a variety of models. e following Schiller-Naumann-Pb equation is employed for the drag force estimation [31]:…”

“…is effect of the turbulent dispersion force results in moving the droplets from high to low concentration areas. Lahey et al launch the following equation to express turbulent dispersion force [31]:…”

Transport Properties and Segregation Phenomena in Vibrating Granular Beds

“…Segregation has also been observed in several configurations when an external driving force, in the form of a vibrating bed, shear cell, rotating drum, or chute flow, is applied to the system. Granular temperature is defined as the specific fluctuation kinetic energy of particles, analogous to the thermodynamic temperature of a gas, and is a key parameter for describing the flow behavior of granular materials (Campbell, 1990;Hsiau et al, 2008;Liao et al, 2015;Ogawa, 1978;Wildman and Huntley, 2000;Zivkovic et al, 2011). Ogawa (1978) proposed the concept of granular temperature to quantify random motions of particles, and this concept has been widely used in related research.…”