CFD Simulation of Dilute Gas-Solid Flow in 90^oSquare Bend

T. A. Mikhail, Walid A. Aissa, S. A. Hassanein, O. Hamdy

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DOI: 10.4236/epe.2011.33031                

Abstract

Gas-solid two-phase flow in a 90? bend has been studied numerically. The bend geometry is squared cross section of (0.15 m × 0.15 m) and has a turning radius of 1.5 times the duct's hydraulic diameter. The solid phase consists of glass spheres having mean diameter of 77 µm and the spheres are simulated with an air flowing at bulk velocity of 10 m/s. A computational fluid dynamic code (CFX-TASCflow) has been adopted for the simulation of the flow field inside the piping and for the simulation of the particle trajectories. Simulation was performed using Lagrangian particle-tracking model, taking into account one-way coupling, combined with a particle-wall collision model. Turbulence was predicted using k-ε model, wherein additional transport equations are solved to account for the combined gas-particle interactions and turbulence kinetic energy of the particle phase turbulence. The computational results are compared with the experimental data present in the literature and they were found to yield good agreement with the measured values.

Keywords

Gas-Solid Two-Phase Flow, Dilute, 90^oBend, CFX

Conflicts of Interest

The authors declare no conflicts of interest.

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