Bubble Motion in Non‐Newtonian Fluids and Suspensions

Abstract The present paper reports a study of the motion of air bubbles in both non‐Newtonian fluids and fluid‐solid (laponite) suspensions. Quantitative information concerning the bubble rise velocity was obtained. In particular, the acceleration mechanism of the rise velocity in fluids was investigated by both a modern technique — Particle Image Velocimetry and a classical method — birefringence visualization. An analytical modeling is proposed to compute the rise velocity of a bubble train with the memory effects. Finally, the visualization demonstrates that the bubble shape and rise velocity in a suspension are very complicated due to the displacement of solid particles by bubbles.