Experimental Investigation of Large Droplet Impact with Application to SLD Icing

Abstract

SLD icing requires the understanding of micrometer-sized droplets impacting at velocities beyond 50 m/s. This paper proposes an experimental investigation of fast impinging large droplets under non-icing conditions. Three aspects of the impact are analyzed: the splash dynamics as a function of the surface nature, the deposition rate, and the secondary drop characteristics for various primary drop characteristics. Examination of images obtained for a clean surface and for a blotter paper surface shows significant differences in terms of the amount of water reemitted. The measurement of the deposition rate confirmed that the dynamics of drop impingement on blotter paper is not the same as impingement on a clean surface. The characterization of the secondary ejected drops shows significant discrepancies with respect to the literature.