Bubbles transport

LBKE can be further modified to capture the multicomponent/multiphase phenomena in GDL as well as GC. This modification also allows modeling the hydrophilic effect such as the bubble transport phenomenon. Lu and Wang visualized the bubble phenomenon in situ using the... 

Pattern—constitution of regime spectrum dependent on material properties bubbling/transport for coarse G/S systems particulate/bubbling/turbulent/ fast/transport for FCC catalyst/air systems particulate only for most L/S systems. 

Pilon L, Fedorov AG, Ramkrishna D, Viskanta R (2004) Bubble transport in three-dimensional laminar gravity-driven flow - mathematical formulation. Journal of Non-CrystaUine Solids 336(2) 71-83... 

Electron tunneling dynamics from electron bubbles in helium clusters strongly depends on the transport dynamics of the electron bubble within the cluster. In normal fluid ( He) and ( He)jy clusters the electron bubble motion is damped, while in (" He)jy superfluid clusters this motion is nondissipative [99]. Accordingly, bubble transport dynamics in ( He) clusters dominates the time scale for electron tunneling from the bubble, providing a benchmark for superfluidity in finite boson systems [245, 251]. In this chapter we address (a) the dynamics of electron tunneling from bubbles in ( He) and ( He) clusters [99, 209, 242-245, 251] and (b) the role of intracluster bubble transport on the lifetime of the bubble states. Our analysis provides semiquantitative information on electron bubbles in (" He) clusters as microscopic nanoprobes for superfluidity in finite quantum systems, in accord with the ideas underlying the work of Toennies and co-workers [99, 242-245]. 

Effective Viscosity. Considerable evidence indicates that in some gas-occupied channels, confined foam bubbles transport as bubble-trains. Effluent bubble sizes from 0.8-/ m2 Berea sandstone reflect expected sizes and their predicted shift with flow velocity (20). Likewise, pregenerated foam is reshaped to the same average exiting bubble size quite independent of the average inlet size (20). As with trapped foam, there is ample direct visual documentation of flowing foam bubble-trains in both micromodels (26) and in bead packs (9, 48). The flow resistance of transporting bubble-trains is best addressed in terms of an effective gas viscosity. 

Chang H. C., Ratulowski J., Bubble transport in a capillary, AICHE Annual Meetings, 1987, 15-20 November, New York, Paper 681. 

Fig. 8.13 Scheme of Kulikovsky s model of bubbles transport in DMFCs (Source [171] reproduced with pmnission of Elsevier)... 

As the usual parabolic velocity profile of pressure-driven Poiseuille flow leads to the flow rate scaling as R whereas the flat velocity profile obtained in pure electroosmotic flow gives rise to a flow rate that scales as R, it can be seen that it is more efficient to drive microchannel flows where R becomes very small using electrokinetic flows as opposed to pressure-driven flow. However, there are some design issues to be considered in electrokinetic bubble transport. 

Interfacial Electrokinetic Flow, Fig. 7 Electrokinetic bubble transport in a capillary. Dimensionless bubble speed represented by the capillary number Ca as a function of the total concentration of ionic surfactant C, [17]... 

The stream of gas bubbles, transports the foreign particles to the surface of the reactor, from where they are skimmed off. If A1 or Fe electrodes are used the respective metal is dissolved with formation as hydroxide which contributes to the coagulation. 

Lundstrom, T.S. Bubble transport through constricted capillary tubes with application to resin transfer molding. Polym. Compos. 1996, 17, 770-779. Lundstrom, T.S. Void collapse in resin transfer molding. Composites A 1997, 28A, 201-214. 

In the past a large variety of flotation ceU designs were used. All cells have to ensure bubble generation, collision of the ink particles with the bubbles, transport of the ink-bubble aggregate to the suspension surface, and foam removal. 

Pilon L, Fedorov AG, Ramkrishna D, Viskanta R (2004) Bubble transport in three-dimensioneil... 

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