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In this study a comparison is made between results from three Eulerian-based computational methods that predict the ice crystal trajectories and impingement on a NACA-0012 airfoil. The computational methods are being developed within CIRA (Imp2D/3D), ONERA (CEDRE/Spiree) and University of Twente (MooseMBIce). Eulerian models describing ice crystal transport are complex because physical phenomena, like drag force, heat transfer and phase change, depend on the particle's sphericity. Few correlations exist for the drag of non-spherical particles and heat transfer of these particles. The effect or non-spherical particles on the collection efficiency will be shown on a 2D airfoil.

Two-dimensional models have been developed to predict and reproduce ice accretion shapes on airfoil profiles. These simulated shapes mostly are similar to experimental forms. However, in some conditions, the ice shapes could present some discontinuity along span showing some ice deposit separated by air inclusion: this deposit is called “lobster tail” or “scallop icing”. The classical 2D approaches fail to predict this kind of ice shapes. The 3D simulation requires to take into account a fully detailed heat and mass balance parameters which scallop accretion is sensitive. For that, the scallop formation was experimentally led on the swept cylinders. An experiment in the icing wind tunnel PAG of the CEPr (The French Engine Test Center) was conducted in order to characterize the phenomenon and find the most relevant criteria. The ice accretions were obtained at different conditions.