scholarly journals Comment on “Kinetic theory models for granular mixtures with unequal granular temperature: Hydrodynamic velocity” [Phys. Fluids 33, 043321 (2021)]

2021 ◽  
Vol 33 (8) ◽  
pp. 089101
Author(s):  
Vicente Garzó
Keyword(s):  
Kinetic Theory ◽  
Granular Temperature ◽  
Granular Mixtures

Kinetic theory of fluidized binary granular mixtures with unequal granular temperature

2000 ◽  
Vol 284 (1-4) ◽  
pp. 265-276 ◽  
Author(s):  
Lu Huilin ◽  
Liu Wenti ◽  
Bie Rushan ◽  
Yang Lidan ◽  
Dimitri Gidaspow
Keyword(s):  
Kinetic Theory ◽  
Granular Temperature ◽  
Granular Mixtures

Analysis of binary and ternary granular mixtures behavior using the kinetic theory approach

2005 ◽  
Vol 151 (1-3) ◽  
pp. 117-125 ◽  
Author(s):  
Hadjira Iddir ◽  
Hamid Arastoopour ◽  
Christine M. Hrenya
Keyword(s):  
Kinetic Theory ◽  
Theory Approach ◽  
Granular Mixtures

Continuum theory for rapid cohesive-particle flows: general balance equations and discrete-element-method-based closure of cohesion-specific quantities

2017 ◽  
Vol 832 ◽  
pp. 345-382 ◽  
Author(s):  
Kevin M. Kellogg ◽  
Peiyuan Liu ◽  
Casey Q. LaMarche ◽  
Christine M. Hrenya
Keyword(s):  
Kinetic Theory ◽  
Discrete Element Method ◽  
Impact Velocity ◽  
Normal Component ◽  
Discrete Element ◽  
Granular Temperature ◽  
Success Factor ◽  
Particle Flows ◽  
The Impact ◽  
Element Method

The continuum description of rapid cohesive-particle flows comprises the population balance, which tracks various agglomerate sizes in space and time, and kinetic-theory-based balances for momentum and granular energy. Here, fundamental closures are provided in their most general form. In previous population balances, the probability (‘success factor’) that a given collision results in agglomeration or breakage has been set to a constant even though it is well established that the outcome of a collision depends on the impact (relative) velocity. Here, physically based closures that relate the success factors to the granular temperature, a (continuum) measure of the impact velocity, are derived. A key aspect of this derivation is the recognition that the normal component of the impact velocity dictates whether agglomeration occurs. With regard to the kinetic-theory balances, cohesion between particles makes the collisions more dissipative, thereby decreasing the granular temperature. The extra dissipation due to cohesion is accounted for using an effective coefficient of restitution, again determined using the derived distribution of normal impact velocities. This collective treatment of the population and kinetic-theory balances results in a general set of equations that contain several parameters (e.g. critical velocities of agglomeration) that are cohesion-specific (van der Waals, liquid bridging, etc.). The determination of these cohesion-specific quantities using simple discrete element method simulations, as well as validation of the resulting theory, is also presented.

The evolution of segregation in dense inclined flows of binary mixtures of spheres

2015 ◽  
Vol 782 ◽  
pp. 405-429 ◽  
Author(s):  
Michele Larcher ◽  
James T. Jenkins
Keyword(s):  
Numerical Simulation ◽  
Binary Mixture ◽  
Kinetic Theory ◽  
Binary Mixtures ◽  
Granular Temperature ◽  
Particle Segregation ◽  
Physical Experiments ◽  
Dense Flows ◽  
Mixture Velocity

We consider the evolution of particle segregation in collisional flows of two types of spheres down rigid bumpy inclines in the absence of sidewalls. We restrict our analysis to dense flows and use an extension of kinetic theory to predict the concentration of the mixture and the profiles of mixture velocity and granular temperature. A kinetic theory for a binary mixture of nearly elastic spheres that do not differ by much in their size or mass is employed to predict the evolution of the concentration fractions of the two types of spheres. We treat situations in which the flow of the mixture is steady and uniform, but the segregation evolves, either in space or in time. Comparisons of the predictions with the results of discrete numerical simulation and with physical experiments are, in general, good.

Kinetic theory based multiphase flow with experimental verification

2018 ◽  
Vol 34 (3) ◽  
pp. 299-318 ◽  
Author(s):  
Dimitri Gidaspow ◽  
Marcelo S. Bacelos
Keyword(s):  
Kinetic Theory ◽  
Annular Flow ◽  
Particle Concentration ◽  
Circulating Fluidized Bed ◽  
Granular Temperature ◽  
Transfer Coefficients ◽  
Tube Radius ◽  
The Core ◽  
Temperature And Pressure ◽  
Energy Balances

Abstract This review is an extension of our 2014 circulating fluidized bed (CFB) plenary lecture. A derivation of multiphase mass, momentum and energy balances is presented, with a review of elementary kinetic theory, to explain the concepts of granular temperature and pressure and the core-annular flow regime commonly observed in CFB. The kinetic theory shows that the particle concentration is given by the reciprocal of a fourth order parabola of dimensional tube radius, in agreement with experiments. Computed flow regimes and heat and mass transfer coefficients in fluidization are also discussed.

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