A novel approach to determine wet restitution coefficients through a unified correlation and energy analysis

Abstract

Wet particle interactions are observed in many applications, for example, pharmaceutical, food, agricultural, polymerization, agglomeration, and coating, in which an accurate evaluation of the wet restitution coefficient (ewet) is crucial to understand the particle flowability, operating conditions and product size distribution. Experiments were performed to measure the wet restitution coefficient by impacting a spherical particle on a stationary plate covered with a thin liquid layer of water or glycerol solution in this work. Furthermore, novel approaches for estimation of ewet were developed using dimensional analysis (using the Buckingham π theorem and regression analysis) in combination with energy budget analysis. In the correlation development, the dominant physical properties of solid and liquid, particle impact velocity and liquid layer thickness are grouped into well‐known dimensionless numbers viz. Reynolds, Weber and Stokes. Whereas in the energy analysis, the energy dissipation rates were determined for five distinct collision phases, that is, dipping, dry collision, undipping, formation and breakage of the liquid bridge, and added mass. The efficacy of the developed approaches was analyzed by comparing obtained results with experiments and an elastohydrodynamic model, and a modified elastohydrodynamic model. © 2014 American Institute of Chemical Engineers AIChE J, 61: 769–779, 2015

Numerical simulation of particle–particle adhesion by dynamic liquid bridge

“…With further increase in the relative collision velocity, e wet showed a steep increase, followed by a gradual increase. This result is qualitatively consistent with an experimental result of collision between a particle and a liquid film, reported in Sutkar et al (2015). From our simulation result, the velocity criterion for the particle adhesion v c was determined as 2.9 m/s.…”

“…Collision between a spherical particle and a stationary liquid film was experimentally analyzed Davis, 2004, 2006;Antonyuk et al, 2009;Sutkar et al, 2015). Antonyuk et al (2009) revealed that at higher viscosity and thicker liquid layer, particle kinetic energy was more likely to be dissipated, indicating that these properties need to be large to enhance agglomeration rate.…”

Experimental determination of parameter effects on the coefficient of restitution of differently shaped maize in three-dimensions

“…A purely elastic contact between rock particles accompanied by energy dissipation was studied in [26]. The energy dissipation rates of wet particles were determined for five distinct collision phases [27].…”

Interface‐resolved simulations of normal collisions of spheres on a wet surface

“…Conversely, when a liquid film is applied, the particle size can have a significant effect on the energy dissipation during wet collisions. The reason for this behaviour has been explained by many researchers, that is, all damping forces (such as surface tension force, drag force, viscous force) depend on the particle diameter either via a power law or by a linear relationship. This is confirmed by the results shown in Figure , which shows the wet restitution coefficient as a function of particle diameter d p for a sphere impacting on a 200 μm liquid layer at an impact velocity v im = 1.3 m/s.…”

“…Later, Kantak et al proposed a simple model on the basis of their experimental data, , with e dry the restitution coefficient under dry conditions. Recently, Sutkar et al developed an energy balance model for the estimation of e wet in terms of well‐known dimensionless numbers, such as the liquid Reynolds number, Stokes number, and Weber number.…”