Dynamics of a slender bubble in a non-Newtonian liquid in an extensional flow

摘要

Mass Transfer between a slender bubble and a non-Newtonian iquid in a simple extensional and creeping flow has been theoretically studied. Exact shapes of slender bubbles in power-law liquids are presented, along with analytical approximations. Steady-state mass transfer is studied assuming the thin concentration boundary layer approximation. The results indicate that the total mass transfer increases with n, the power4aw parameter, due to larger surface areas in dilatant liquids compared to pseudoplastic liquids for a similar imposed flow. The relevance of this work to the processes of polymer melt devolatilization and the production of polymer foams is discussed.