Multiphase flow and mixing in dilute bubble swarms

Abstract

in Wiley Online Library (wileyonlinelibrary.com).High-fidelity three-dimensional (3-D) simulations of multiphase flow and mixing in dilute bubble swarms were performed using the Euler-Lagrange simulation approach. Included was species transport, as well as complex chemical reactions in the simulations. It was found that the algebraic SGS model satisfactory predicts experimental data for the mean flow field. A detailed description of multiphase flow was used and developed to simulate the time evolution of scalar and reactive mixing in a bubble column. An analysis involving the scale of segregation U, a metric that characterizes the mean driving force for mixing, is applied for the first time to multiphase flow. The study shows that U is inversely proportional to the bubble diameter at constant gas-feed rate, but only a weak function of the gas-feed rate. Also, we observed significant differences of mixing metrics in reactive and nonreactive systems. V V C 2010 American Institute of Chemical Engineers AIChE J, 56: 2421AIChE J, 56: -2445AIChE J, 56: , 2010

Coalescence and Break‐Up in Bubble Columns: Euler‐Lagrange Simulations Using a Stochastic Approach

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Experiments and modelling of a draft tube airlift reactor operated at high gas throughputs

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Effect of Vertical Vibration on the Mixing Time of a Passive Scalar in a Sparged Bubble Column Reactor

“…The resulting diffusion coefficients were in a good agreement with experimental data. Radl and Khinast [18] studied mixing in the presence of mass transfer and chemical reaction using a numerical simulation of a diluted bubble swarm in a thin rectangular bubble column. This study provided insights into the physics of bubble mixing by introducing a quantitative measure of the mixing driving force Φ (i.e., scale of segregation).…”