Visualization Experiments
Visual studies (Hele-Shaw models) are limited to 2D models due to difficulties in obtaining detailed images using 3D models (Fang and Babadagli 2016a-b-c) applying 2D analysis can provide the information necessary for understanding the fundamentals of multiphase fluid flow (Maxworthy 1986; Arnéodo et al. 1989; Hamida and Babadagli 2007; Al-Bahlani and Babadagli 2012; Jha et al. 2013; Fu et al. 2017; Lee et al. 2019). In order to develop insights into understanding the analogy between emulsion instability associated fingering and partial miscibility induced fingering instabilities, we applied a two-dimensional Hele-Shaw model derived from a large quantity of literature available on Hele-Shaw flows for miscible and immiscible flooding. Chemical combinations selected from the screening include AS: Anionic Surfactant, CS: Cationic Surfactant, NF: NanoFluid, and P: Polymer (Table 1 ). Their chemical types are CS: CTAB, NF: Silica, AS: Alcohol Propoxy Sulfate, and P: Xanthan gum. Their associated information (such as active matter, commercial name) along with the detailed experimental set up can be found in Lee et al. (2020). A constant flow rate of 0.1 ml/min was selected for each injection case. Chemical combinations were selected based on their ability to generate droplets during the experiment.