Modeling aerosol scavenging by drops: from microphysical CFD simulations to a global collection kernel

Scavenging aerosol particles by droplets is an efficient way of removing hazardous particles from gases. Therefore, predicting removal rates by means of a realistic collection kernel is a purpose in several research fields like environment, industrial or atmospheric science. An effective scavenging kernel must take into consideration several coupled collection mechanisms such as Brownian scavenging, phoretic and electrostatic forces leading to capture and inertial impaction/interception which depend on the flow regime around the drop. Examining the literature shows the lack of universality of scavenging kernels but also the lack of precise numerical or experimental reference data enabling a more general correlation for the scavenging kernel to be derived. We propose to improve available reference data using numerical scavenging experiments and then to derive a universal scavenging kernel from these new scavenging efficiencies.