Numerical investigation and modelling of the venous injection of sclerosant foam
Authors: Wong K. C. , Armfield S. W. , Williamson N. 
Published: December 2019

Sclerosant foam, a mixture of a surfactant liquid and air, is injected directly into varicose veins as a treatment that causes the vein to collapse. This investigation develops a model that will allow the medical specialist to visualise how the sclerosant foam will interact with the blood and behave within the vein. The process is simulated using a multiphase computational fluid dynamics model with the sclerosant foam considered as a two-phase non-Newtonian power law viscosity liquid. The governing multiphase equations are solved using an Eulerianâ â€“â Eulerian approach coupled with a population balance model to predict the bubble size distribution within the flow field. The computational results demonstrate similar flow characteristics and flow features to an available set of experimental results. The model predicts the mixing layers between the sclerosant foam and the ambient fluid, and the sclerosant liquid and the ambient fluid, as well as the sclerosant liquid coverage on the vein wall and the bubble size distribution within the vein. These quantities are of interest to medical specialists allowing them to assess the treatment feasibility and safety before treating the patients.

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