An LBM-PNM framework for immiscible flow: With applications to droplet spreading on porous surfaces. (8th June 2020)

• Record Type: Journal Article
• Authors: Suo, Si; Liu, Mingchao; Gan, Yixiang
• Is Part Of: Chemical engineering science. Volume 218(2020)
• Publication Date: 2020-06-08
• Subjects: Multiphase flow -- Multiscale modelling -- Lattice Boltzmann method -- Pore-network method -- Droplet behaviour; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2020.115577
• Languages: English
• ISSNs: 0009-2509

Abstract

Graphical abstract: Highlights: A robust algorithm coupling LBM and PNM was developed for modelling two-phase flow. The proposed algorithm has been validated against the experimental observation. The competition between droplet spreading and matrix imbibition was further studied. Abstract: The behaviour of droplets on porous media, combining the spreading above and imbibition into the medium, is of foundational interests for a series of applications. In this work, we combine the lattice Boltzmann method (LBM) and pore-network method (PNM) to develop an efficient and robust numerical framework in which the coarse-scale multiphase transport in porous media are modelled by the PNM while the fluid dynamics containing multiple components are resolved by the LBM. An effective transport mechanism has been implemented to ensure mass conservation and pressure continuity across the interface. This method is ideally adapted to flow domains, with two distinguishable characteristic length-scales. The numerical framework is validated by comparison with experimental observations of droplets on flat porous surfaces. Moreover, the behaviour of droplets on non-flat porous surfaces has been also investigated, demonstrating the influence of surface curvature on the competing mechanisms of droplet spreading and imbibition.