Fig. 3: Propulsion mechanism.
From: Galloping Bubbles
a, b Experimental visualization of flow fields around a galloping bubble reveals the interface (a) pushing ambient fluid towards the bubble’s back when moving downwards, and (b) drawing fluid from its front when moving upwards (Supplementary Movie 4). c Rectilinear galloping bubbles obey a power scaling law for the dimensionless galloping speed V/ωR in terms of the dimensionless driving (A−AG)/R and Weber number We, which collapses the simulated hemispherical bubbles with a power α = 0.29. d The relative deviation between the galloping speed in simulated hemispherical bubbles, Vs, and that expected from inviscid theory, Vt, decreases with the Reynolds number, indicating that galloping bubbles leverage inertial forces for propulsion.
