The relation between the Taylor bubble motion and the velocity field aheadof it

The motion of a single elongated (Taylor) bubble propagating in a transpare nt vertical pipe is studied experimentally in stagnant liquid, as well as i n upward and downward liquid flow. Digital image processing of a sequence o f video images serves as the main experimental method for the study of the Taylor bubble motion. In addition, the distribution of the velocities in fr ont of the bubble and in the liquid film is measured using Particle Image V elocimetry. The relation between the Taylor bubble motion and the velocity field in front of it is discussed. (C) 1999 Elsevier Science Ltd, All right s reserved.