ABSTRACT

This contribution explores the nature and prediction of the forces on dispersed phase elements (particles, bubbles, droplets) in dispersed two-phase flows. The difficulties in parameterization of the force on a sphere embedded in a shear or straining flow at finite Reynolds number are illustrated by considering several examples (contaminated bubble in a vortex, particle moving at an angle through a straining ambient flow, particle moving freely in a shear flow). The challenges in prediction of the respective forces are reviewed and the significance of temporal acceleration and spatial variation in the flow explored.