Wet foam flow under a fence located in the middle of a horizontal duct of square section

We investigate the flow characteristics of an aqueous foam in a horizontal duct of square section, in presence of a fence. This experimental study consists in determining the frictional pressure loss, the dynamics of the wet foam flow by PIV, the static drainage and the thickness of the underlying liquid film in the vicinity of the singularity. Near this latter, the singular pressure loss is deduced by extrapolation using the measurements of the frictional pressure evolution obtained in the upstream and downstream of the fence. For each chosen quality of the foam, the average and the fluctuating velocities using PIV method were obtained near the singularity from a series of 150 instantaneous snapshots. Concerning the static drainage and the underlying liquid film thickness, experimental data was obtained in order to well understand the fence effects on the foam texture in the immediate vicinity of this latter. Through this singularity, all these experimental results allowed to give the fence effects on the foam and the general tendency of the foam flow reorganisation.