Chemical Engineering Science, Vol.157, 138-146, 2017
Cutting bubbles with a single wire
Many gas liquid solid contactors, such as trickle bed and bubble slurry columns, suffer from heat and mass transfer limitations. To overcome these limitations, new micro-structured bubble column reactor is proposed. In this reactor, a catalyst coated wire mesh is introduced in a bubble column to cut the bubbles and enhance the interface dynamics. In this work, the effect of the simplest form of a wire mesh, i.e. a single wire, on a single bubble is studied experimentally and using Direct Numerical Simulations. The combined Volume of Fluid and Immersed Boundary method shows a good agreement with the experimentally obtained bubble sizes after cutting, bubble shapes, trajectory and bubble rise velocities. Only small differences are found in the bubble rise velocity in close proximity of the wire. Various effects were determined both experimentally and numerically: the effects of Eotvos number, Morton number, bubble rise velocity, wire diameter and the obliqueness of the bubble wire interactions. From the results, it can be concluded that the main influences on the bubble cutting are the Eotvos number, the wire diameter and the obliqueness of the interaction. However, a quantitative closure for the bubble cutting using single wires could not be obtained. (C) 2016 Elsevier Ltd. All rights reserved.