TY - JOUR
T1 - Chromodynamic Lattice Boltzmann Method for the Simulation of Drops, Erythrocytes, and Other Vesicles
AU - Spendlove , J.
AU - Xu , X.
AU - Schenkel , T.
AU - Gunn , J. P.
AU - Halliday , I.
JO - Communications in Computational Physics
VL - 1
SP - 283
EP - 309
PY - 2023
DA - 2023/02
SN - 33
DO - http://doi.org/10.4208/cicp.OA-2022-0042
UR - https://global-sci.org/intro/article_detail/cicp/21435.html
KW - Lattice Boltzmann, membranes, vesicles.
AB - <p style="text-align: justify;">Recently, we have validated a three-dimensional, single framework multicomponent lattice Boltzmann method, modified to generate vesicles (rather than drops)
[“Three-dimensional single framework multicomponent lattice Boltzmann equation
method for vesicle hydrodynamics,” Phys. Fluids 33, 077110 (2021)]. This approach
implements an immersed boundary force distribution, characterised by bending rigidity, surface tension, preferred curvature and conserved membrane area, in which work
we successfully validated isolated vesicle flows against other methodologies and experiment. Like most immersed boundary algorithms, our method relies on numerical
computation of high-order spatial derivatives and an intricate body force density. The
next step is to verify that it has sufficient numerical stability to address the anticipated
application of high volume fraction flows of highly deformable objects in intimate interaction. It is this in silico verification – of both the class of fluid object attainable and
the stability of the later in strong, straining and shearing flows which is at issue, here.
We extend our method to simulate multiple variously deflated vesicles and multiple
liquid droplets still within a single framework, from which our fluid objects emerge as
particular parameterisations. We present data from simulations containing up to four
vesicles (five immiscible fluid species), which threshold verifies that simulations containing unlimited fluid objects are possible [“Modeling the flow of dense suspensions
of deformable particles in three dimensions,” Phys. Rev. E 75, 066707 (2007)]. These&nbsp;data also assure the ability of our immersed boundary forcing to preserve the character and integrity of fluid objects in interactions characterised by large local velocity
gradients (intimate squeezing, shearing and elongational straining). Throughout, we
take interfacial or membrane area, $A,$ as a proxy for stability and physical veracity.</p>