%0 Journal Article %A Sommerfeld, Martin %A Lain, Santiago %D 2009 %I Begell House %N 1-2 %P 123-140 %R 10.1615/MultScienTechn.v21.i1-2.100 %T FROM ELEMENTARY PROCESSES TO THE NUMERICAL PREDICTION OF INDUSTRIAL PARTICLE-LADEN FLOWS %U https://www.dl.begellhouse.com/journals/5af8c23d50e0a883,3003408060e425f0,162ea8ae515b7647.html %V 21 %X In particle-laden flows, the overall flow structure and the relevant process parameters, e.g., pressure drop or separation efficiency, are strongly affected by the elementary processes occurring on the scale of the particles. Therefore, a detailed modeling of these microscale phenomena is required when anticipating reliable numerical predictions. Here the Euler/Lagrange approach was further developed in order to calculate confined particle-laden flows in pneumatic conveying lines and gas cyclones. Special emphasis is placed on the influence of particle-wall collisions and wall roughness as well as interparticle collisions with possible agglomeration on the developing two-phase flow structure and the resulting process parameters. The models and the numerical method were validated based on the pressure drop measured along a 6-m horizontal channel. The agreement was found to be excellent for different particle sizes, mass loading, and wall roughness. The numerical predictions of a horizontal pipe flow revealed that due to a wall roughness-induced focusing of particle trajectories toward the core of the pipe, a secondary flow in the pipe cross section develops. Moreover, it was found that the additional pressure drop due to the particles in the pipe flow was higher than that in the channel due to the different wall collision behavior. The numerical calculations of particle separation in a gas cyclone revealed the importance of a detailed modeling of interparticle collisions and particle agglomeration on the resulting grade efficiency curves. Agglomeration improves the separation of fine particles substantially. %8 2009-05-29