Figure 2—-Summary of viscous fingering experiments (based on
Lee et al. 2020) (a): Hele-Shaw images (b): Micrographs of produced
samples *XG: Xanthan Gum, AS: Anionic surfactant.
In our previous visual analysis work using steam and polysorbate at
thermal conditions at 200°C (Bruns and Babadagli 2020) and cationic
surfactant at non-thermal conditions (Lee et al. 2020), droplet
generation could be seen in both cases (following the predicted
tip-splitting fingers) bearing a striking resemblance in their
appearance to the droplet development encountered in partially-miscible
fluid flow (Figure 3 ).