Sticking–Erosion Model for Ice Crystal Icing Using Particle Size Distribution

Abstract

Ice crystal icing has been identified as a threat to aviation safety, with hundred engine power loss events having been experienced since the 1990s. This has led to new type certification requirements for the industry to demonstrate safe operation in these environmental conditions. The sticking and erosion behaviors of ice crystals are critical factors in ice crystal icing. However, many existing sticking–erosion models are developed based on ice crystals using the mean particle diameter for experimental tests that have a broad distribution of size. This leads to biasing when a different distribution with the same mean particle diameter is considered. This paper develops a new sticking–erosion model that accounts for the particle size distribution seen in experimental data typical of glaciated icing conditions. The results of model are compared to experimental accretion data over a range of melt ratio, Mach number, test article geometry, and particle size distribution. The predicted accretion profiles agree reasonably with experiments. The mean difference of the ice tip thickness between predictions and experiments is approximately 2.8 mm, compared to the mean ice tip thickness of 12.0 mm. The plateau effect of melt ratio on accretion is adequately predicted. More severe accretion of the small- to medium-sized ice crystals is observed. The predicted net accretion efficiency of large particles ([Formula: see text]) is small and is shown to be negative due to the effect of erosion. This concurs with the experimental observation that the presence of large ice particles is critical to reducing the ice accretion rate.