2026 · Conference
Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden, 2–6 November 2026. One contribution: the lift force on single bubbles rising in aqueous ionic-liquid solutions.
Oral presentation
22nd Multiphase Flow Workshop, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany, 2–6 November 2026.
The shear-induced lift force decides how bubbles migrate sideways in a gas–liquid shear flow, and CFD models of bubble columns need it — but the established lift-coefficient correlations do not hold once an ionic liquid sits at the bubble interface. The lift coefficient of single air bubbles, 2 to 6.5 mm across, was measured with the shear-flow method in aqueous BMIM-BF₄ at 0.1, 1, 5 and 10 wt %. Where clean water changes sign above a diameter of about 5.2 mm, the bubbles in the ionic-liquid solutions keep a positive lift coefficient (about 0.2–0.6) over the whole range, and unlike conventional surfactants they show no decline toward zero as the concentration rises. A first step toward a lift-coefficient correlation for ionic-liquid systems.