Investigation of two-phase flow during liquid displacement in microchannels : experiments and CFD simulations

Autor: Lu, Yu
Rok vydání: 2018
Předmět:
Druh dokumentu: Electronic Thesis or Dissertation
Popis: Microfluidic systems attract attention because the benefit they offer such as very high surface area to volume ratio and the precise control of the flow features or droplets formation. However, the study of displacement flows has not been systematically explored. This thesis presents a study of the behaviour of liquid-liquid two-phase flows in microchannel during the displacement of one liquid by another. Liquid displacement using immiscible and miscible fluid pairs were carried out. The kinematic viscosities of the fluids used range from 1 to 100 cSt. Three types of straight channel and a T-junction channel were tested. The flow activities at the fluids interface, with the addition of surfactants, were mainly investigated. Flow regimes were identified and their occurrence was illustrated via flow pattern maps. CFD simulations are applied largely in the study of fluid mechanics aiming to confidently predict flow behaviour from computational methods. The experimental results were used to validate CFD simulations carried out using the Fluent package incorporating the VoF model. Good agreement between simulation and experiment results was achieved.
Databáze: Networked Digital Library of Theses & Dissertations