Computations of multi-fluid flows
Proceedings of the eleventh annual international conference of the Center for Nonlinear Studies on Experimental mathematics : computational issues in nonlinear science: computational issues in nonlinear science
A front-tracking method for dendritic solidification
Journal of Computational Physics
On the stability of Godunov-projection methods for incompressible flow
Journal of Computational Physics
Journal of Computational Physics
Journal of Computational Physics
Journal of Computational Physics
A front-tracking method for the computations of multiphase flow
Journal of Computational Physics
A second-order-accurate symmetric discretization of the Poisson equation on irregular domains
Journal of Computational Physics
Journal of Computational Physics
A surfactant-conserving volume-of-fluid method for interfacial flows with insoluble surfactant
Journal of Computational Physics
A front-tracking method for computation of interfacial flows with soluble surfactants
Journal of Computational Physics
A conservative SPH method for surfactant dynamics
Journal of Computational Physics
A hybrid numerical method for interfacial fluid flow with soluble surfactant
Journal of Computational Physics
A diffuse-interface method for two-phase flows with soluble surfactants
Journal of Computational Physics
Journal of Computational Physics
A level-set continuum method for two-phase flows with insoluble surfactant
Journal of Computational Physics
An embedded boundary method for soluble surfactants with interface tracking for two-phase flows
Journal of Computational Physics
Hi-index | 31.49 |
Based on a front tracking scheme, we have presented a comprehensive algorithm for the study of a deformable bubble moving in a tube in the presence of a soluble or an insoluble surfactant. The emphasis here is on the dynamic adsorption of the soluble surfactant which non-linearly alters the surface tension, and this in turns affects the flow and transport in a complicated way. Furthermore, since a bubble-liquid interface is being examined, there is a need to accommodate a concentration jump across the interface in the evaluation of flow and transport. Standard numerical procedures need to be modified to accommodate this feature. Based on the physics governing the problem, an axisymmetric formulation is found to be adequate and is thus considered. The adsorption scheme for the soluble surfactant is carefully designed such that the total mass of the surfactant is well conserved, and the mass flux is accurately resolved by using an interface indicator function. This represents an advance in treating problems of this class. Tests on the efficacy of various aspects of the algorithm have been carried out. The algorithm has the flexibility of studying different models for adsorption/desorption and surfactant surface tension models, such as the Langmuir and the Frumkin models. These models have significant practical relevance. The numerical results obtained are qualitatively consistent with results where available. The results presented include an example of Marangoni flow which causes a bubble to propel out of its initial static location due to the development of a surface tension gradient. It is also shown that the bubble motion in Poiseuille flow may be significantly slowed down due to the presence of a soluble surfactant in the bulk medium. In that case, the Marangoni induced motion is in a direction opposite to that driven by the bulk pressure. Our study indicates that as the location of the adsorptive interface gets closer to the tube wall, the bulk fluid in the vicinity of the interface may become depleted of surfactant, an observation that has particular significance in understanding gas embolism and for developing therapeutic measures.