Reynolds-Averaged Two-Fluid Model prediction of moderately dilute fluid-particle flow over a backward-facing step

A mathematical model is proposed to describe the gas-particle flow in a bed packed with particles. The model is in essence the same as the two fluid model developed on the basis of the space-averaged theorem but extended to consider the interactions among the gas, powder and packed particles and the static and dynamic holdups of powder. In particular, a method is proposed to determine the boundary between powder mobile and non-mobile zones, i.e. the profile of powder accumulation zone. The validity of the numerical modelling is examined by comparing the predicted and measured distributions of powder accumulation under various flow conditions.

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Dilute gas-particle flow through thin and thick orifice: a computational study through two fluid model

Particulate Science And Technology ◽

10.1080/02726351.2019.1566939 ◽

2019 ◽

Vol 38 (6) ◽

pp. 711-725 ◽

Cited By ~ 4

Author(s):

Santosh Kumar Senapati ◽

Sukanta Kumar Dash

Keyword(s):

Computational Study ◽

Fluid Model ◽

Particle Flow ◽

Dilute Gas ◽

Flow Through ◽

Two Fluid Model ◽

Two Fluid

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Implementation of Two-Fluid Model for Dilute Gas-Solid Flow in Pipes With Rough Walls

Journal of Fluids Engineering ◽

10.1115/1.4026282 ◽

2014 ◽

Vol 136 (3) ◽

Cited By ~ 3

Author(s):

Ashraf Uz Zaman ◽

Donald John Bergstrom

Keyword(s):

Surface Roughness ◽

Gas Phase ◽

Numerical Study ◽

Fluid Model ◽

Vertical Tube ◽

Particle Flow ◽

Layer Model ◽

Two Layer Model ◽

Two Fluid Model ◽

Two Fluid

A numerical study was carried out to investigate the performance of a two-layer model for predicting turbulent gas-particle flows in rough pipes. An Eulerian–Eulerian two-fluid formulation was used to model both the gas and solid phases for turbulent gas-particle flow in a vertical tube. The stresses developed in the particle phase were calculated using the kinetic theory of granular flows while the gas-phase stresses were described using an eddy viscosity model. The two-fluid model typically uses a two-equation k-ɛ model to describe the gas phase turbulence, which includes the suppression and enhancement effects due to the presence of particles. For comparison, a two-layer model was also implemented since it has the capability to include surface roughness. The current study examines the predictions of the two-layer model for both clear gas and gas-solid flows in comparison to the results of a conventional low Reynolds number model. The paper specifically documents the effects of surface roughness on the turbulence kinetic energy and granular temperature for gas-particle flow in both smooth and rough pipes.

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Eulerian modelling of gas–solid flows with triboelectric charging

Journal of Fluid Mechanics ◽

10.1017/jfm.2018.361 ◽

2018 ◽

Vol 848 ◽

pp. 340-369 ◽

Cited By ~ 10

Author(s):

Jari Kolehmainen ◽

Ali Ozel ◽

Sankaran Sundaresan

Keyword(s):

Fluid Model ◽

Particle Flow ◽

Effective Work ◽

Effective Work Function ◽

Electrostatic Charges ◽

Triboelectric Charging ◽

Two Fluid Model ◽

Discrete Element Simulations ◽

Two Fluid ◽

The Continuum

Particles subjected to flow are known to acquire electrostatic charges through repeated contacts with each other and with other surfaces. These charges alter gas–particle flow behaviour at different scales. In this work, we present a continuum framework for analysing the interplay between tribocharging and the flow of a monodisperse assembly of particles characterized by a single effective work function. Specifically, we have derived the continuum, kinetic theory transport equations for gas–particle flow and local-averaged charge on particles directly from the Boltzmann equation. We also derive the auxiliary conditions to capture tribocharging at bounding conducting walls. The resulting two-fluid model with tribocharging and boundary conditions has then been validated against results from discrete element simulations that have been specially designed to probe specific terms in the models.

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