Numerical investigation into the effects of wall roughness on a gas–particle flow in a 90° bend

• Published in: International journal of heat and mass transfer Vol. 51; no. 5; pp. 1238 - 1250
• Main Authors: Tian, Z.F., Inthavong, K., Tu, J.Y., Yeoh, G.H.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.03.2008; Elsevier
• Subjects: 90° bend; CFD; Computational methods in fluid dynamics; Exact sciences and technology; Flows in ducts, channels, nozzles, and conduits; Fluid dynamics; Fundamental areas of phenomenology (including applications); Gas–particle flow; Multiphase and particle-laden flows; Nonhomogeneous flows; Particle–wall collision; Physics; Wall roughness; CFD; 90° bend; Gas–particle flow; Particle–wall collision; Wall roughness; Gas particle flow; Rough wall; Pipe flow; Computational fluid dynamics; Particle motion; Digital simulation; Roughness; Computation code; Pipe bend; Dilute phase; Particle suspension; Phase velocity; Two-phase flow; Modelling; Mesh generation
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2007.12.005

This paper presents a numerical study of a dilute gas–particle flow in a 90° bend by employing a Lagrangian particle-tracking model combined with a particle–wall collision model and a stochastic wall roughness model. The major objective of this study was to investigate the effects of wall roughness on the particle flow properties. The numerical simulation revealed that wall roughness significantly reduced the ‘particle free zone’ and smoothed the particle number density profiles by altering the particle rebounding behaviours. It was also found that wall roughness reduced the particle mean velocities and also increased the particle fluctuating velocities in both streamwise and transverse directions.