This paper presents Ice Crystals particles trajectory simulations based on models representative of aircraft engines flying through realistic Ice Crystals clouds. The current study pursues of the work performed by Safran Aircraft Engines in the framework of the High Altitude Ice Crystals (HAIC) European research project. Results of the HAIC/High Ice Water Content (HIWC) projects flight campaigns are used to characterize the atmospheric environment in the Ice Crystals clouds. The present work benefits from the mixed-phased and glaciated particles trajectory modeling capabilities available in ONERA's icing numerical tools. Simulations are run on two distinct geometries: a generic engine Inlet & Fan, and a generic Fan & Low Pressure Compressor. The first configuration allows the effects of centrifugation and fragmentation on particle concentrations at the engine's primary flow inlet. The influence of particle size is also studied. The second geometry provides qualitative information on preferential accretion sites within the engine. Simulation results obtained for this configuration are consistent with experimental observations of the so-called plateau effect.

A joint Airbus & Snecma study on aero-thermal methodology applied to nacelle compartment is presented. Both partners have used their own simulation tools and compared their results with a real engine configuration to highlight the temperature heterogeneities on the engine casing and characterize equipment thermal fields. From the CFD, the structure of the flow has been consolidated in a cavity without equipments. The impact of equipment items on flow behavior has been studied in a second step. From a thermal aspect, the weight of both radiative and convective transfers has been estimated. Comparisons with engine thermocouple data show that the difference on average metal temperatures per station is less than 10% whereas the temperature gradient are underestimated in a range of [10–30]°C.

In the framework of STORM, a European project dedicated to icing physics in aircraft engines, a cascade rig representative of an anti-iced engine inlet was tested in icing conditions. This mock-up integrates two rows of vanes, the upstream one being anti-iced using an Electro-Thermal Ice Protection System (ET-IPS). Experimental tests were performed to reproduce the following phenomena: runback water and droplet re-emission from anti-iced vanes, and accretion of re-emitted droplets on downstream vanes. A complete experimental database was generated, including the characterization of ice accretion shapes, and the characterization of electro-thermal anti-icing system (power limit for apparition of the runback water or ice accretion). In the current study, these data are compared to droplet trajectory simulation and ice accretion simulation results, for validating icing tools in engine environment. Influence of one-step and multi-step approaches have been investigated.