Articles | Volume 17, issue 6
https://doi.org/10.5194/acp-17-4159-2017
https://doi.org/10.5194/acp-17-4159-2017
Research article
 | 
28 Mar 2017
Research article |  | 28 Mar 2017

Experimental evidence of the rear capture of aerosol particles by raindrops

Pascal Lemaitre, Arnaud Querel, Marie Monier, Thibault Menard, Emmanuel Porcheron, and Andrea I. Flossmann

Abstract. This article presents new measurements of the efficiency with which aerosol particles of accumulation mode size are collected by a 1.25 mm sized raindrop. These laboratory measurements provide the link to reconcile the scavenging coefficients obtained from theoretical approaches with those from experimental studies. We provide here experimental proof of the rear capture mechanism in the flow around drops, which has a fundamental effect on submicroscopic particles. These experiments thus confirm the efficiencies theoretically simulated by Beard (1974). Finally, we propose a semi-analytical expression to take into account this essential mechanism to calculate the collection efficiency for drops within the rain size range.

Download
Short summary
We present new measurements of the efficiency with which aerosol particles are collected by raindrops. These measurements provide the link to reconcile the scavenging coefficients obtained from theoretical approaches with those from experimental studies. We provide proof of the rear capture that is a fundamental effect on submicroscopic particles. Finally, we propose an expression to take into account this mechanism to calculate the collection efficiency for drops within the rain size range.
Altmetrics
Final-revised paper
Preprint