Imbibition dynamics in an open-channel capillary with holes
Journal
Journal of Molecular Liquids
Journal Volume
349
Date Issued
2022
Author(s)
Abstract
Spontaneous capillary flow is generally described by Washburn's equation. However, the modification must be made for imbibition dynamics in an open channel. Moreover, the presence of the holes in the capillary for flow division or bifurcation complicates the outcome of the imbibition process. In this work, capillary imbibition into a two-rail channel with/without holes is investigated by many-body dissipative particle dynamics (MDPD). The influences of channel height (h), channel width (w), hole size (wh), and surface wettability (θY) on the imbibition rate are examined. For two-rail channel without holes, the simulation results agree reasonably with Washburn's equation with the correction 1-(h/w)/cosθY. The penetration rate grows with reducing the channel height or enlarging the channel width. However, in the presence of holes, the wicking dynamics is slowed down and four types of outcomes are observed: “covering”, “separation”, “pass/stop”, and “stoppage”. These states depend on the size and (symmetric or asymmetric) position of the rectangular hole. Finally, the phase diagrams which vary with θY, wh/h, and w/h are constructed. The domains of those states agree reasonably with the equations acquired simply from the analyses of surface free energy. ? 2021 Elsevier B.V.
Subjects
Channel with holes
Imbibition dynamics
Phase diagram
Two-rail open channel
Washburn's equation
Free energy
Open channel flow
Capillary imbibition
Channel height
Channel widths
Channel with hole
Hole size
Imbibition dynamic
Imbibition process
Open channels
Washburn equation
Phase diagrams
Type
journal article