  The physical mechanism of the oriented shift and inverse of eccentric
globules in a modest extensional flow are investigated in this paper. Through
this work, a shift of the globule, which is driven mainly by the asymmetric
interfacial curvature, not by the outer drag, is disclosed. The asymmetric
layout of the daughter droplet leads to the asymmetric drags from the
continuous phase and the asymmetric deformation of the globule with different
interface curvatures. As the inner droplet has both enhancing and suppressing
effect on the globule deformation, the interface curvatures will vary when
changing the relative size and location of the inner droplet. This curvature
difference results in the asymmetric pressure distribution and circulation
inside the globule. Eventually, the interaction of the inner driving force
(pressure differences) and the outer drags causes the oriented shift and
inverse of the globule. The shift direction is affected not only by the
structural asymmetry parameter (eccentricity), but also by some flow features
such as the capillary number. The results obtained here might enlighten
potential applications for the movement of soft globules driven by curvature
differences.
