Experimental investigation of aerosol separation in a rising Taylor bubble

Aerosol transport in rising air bubbles finds application in the removal of micro-pollutants from gases. Its theoretical investigation is mostly limited to small air bubbles because they remain spherical. For bubbles larger than a few centimeters, the gas-liquid interface oscillates in an unpredictable way. This affects the flow on both sides of the interface and ultimately the aerosol-to-liquid capture. We presently investigate aerosol separation in rising Taylor bubbles. Such bubbles have a highly reproducible elongated shape, easily extending to 20 cm in length, and are ideal candidates for model validation. Over one hundred separation experiments with an aerosol size ranging from 1 to 5 μ m are presented. This regime, known as inertia-dominated, is of particular scientific interest because the aerosol transport is strongly dependent on the air flow inside the bubble. A simple and semi-analytical formulation reducing all our experimental results is proposed. • Aerosol separation in rising Taylor bubbles is studied experimentally. • Separation efficiency decreases with bubble elongation. • We propose a semi-analytical model for inertia-dominated aerosol separation. • The model reliably captures the effect of bubble elongation on efficiency.