About the authors
| First name, Middle name, Last name, Scientific degree, Scientific rank, Current position. Full and brief name of the organization, The organization address. | Malanichev I.V. – candidate of technical sciences E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it Akhmadiev F.G. – doctor of technical sciences, professor E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it Kazan State University of Architecture and Engineering The organization address: 420043, Russia, Kazan, Zelenaya st., 1 |
| Title of the article | Stochastic model of concentrated emulsion flow in microchannel |
| Abstract. | Invert water-hydrocarbon emulsions as a dispersions of microdroplets of water in the hydrocarbon (oil, diesel fuel, bitumen, tar) are widely used in the oil and building industry. Dynamic flow blocking effect is detected during the flow of concentrated (the volume fraction of the continuous phase of less than 30 %) invert emulsions in microchannels (capillaries, cracks, pores). Flow rate over time is slowed by several orders of magnitude despite the permanent pressure drop. It can not be explained by capillary effects, since the size of the microdroplets of the emulsion is much smaller than the characteristic transverse dimensions of the microchannels. The nature of this phenomenon is not clear enough. Attempts of theoretical description of the effect of locking is based on assumption about of elastic interaction of emulsifier films surrounding microdroplets acquiring property of «rigidity» during deformation. A model of the flow of highly concentrated emulsions as a two-phase medium is considered for the study of the processes leading to the dynamic flow blocking effect. The movement of a continuous phase is determined by the lattice Boltzmann method, as droplet phase motion is based on a stochastic model. Emulsion droplets are considered as dispersed particles whose motion is the sum of the transfer by fluid flow and free roaming. Droplets may be in the free and bound states. The transition to a bound state occurs above a given threshold concentration of drops in the node. Fluid flow through a node filled with drops in the bound state is regarded as filtering. Simulation of the emulsion flow in microchannel was carried out and processes of emulsion structuring during changing the flow character from free flow to filtration were investigated. It is shown that the longitudinal structures are formed before locking and transverse structures after. The simulation results are consistent with experimental data. |
| Keywords. | lattice Boltzmann method, stochastic simulation, emulsion, effect of dynamic blocking, filtering. |
| For citations: | Malanichev I.V., Akhmadiev F.G. Stochastic model of concentrated emulsion flow in microchannel // Izvestiya KGASU. 2015. №2(32) P.386--1. |
