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Within the European Integrated Project NACRE (New Aircraft Concept REsearch) led by Airbus, a team of research centers and universities developed a multidisciplinary flying testbed called IEP (Innovative Evaluation Platform). Under the form of a dynamically scaled model of a future civil transport aircraft, its role is to assist engineers during the assessment of flight dynamics characteristics and noise reduction capabilities. After the feasibility study during which potential scientific and economical benefits of such new test facility have been identified, the team decided to design and manufacture the IEP. Because of the dual aspect of the system (it is a flying unmanned aerial vehicle and a test facility), an extensive requirement analysis has been carried out by the partners in order to identify the necessary operational modes and their associated navigation and control strategies.

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.

Icing is a major hazard for aviation safety. Over the last decades an additional risk has been identified when flying in clouds with high concentrations of ice-crystals where ice accretion may occur on warm parts of the engine core, resulting in engine incidents such as loss of engine thrust, strong vibrations, blade damage, or even the inability to restart engines. Performing physical engine tests in icing wind tunnels is extremely challenging, therefore, the need for numerical simulation tools able to accurately predict ICI (Ice Crystal Icing) is urgent and paramount for the aeronautics industry, especially regarding the development of new generation engines (UHBR = Ultra High Bypass Ratio, CROR = Counter rotating Open Rotor, ATP = Advanced Turboprop) for which analysis methods largely based on previous engines experience may be less and less applicable. The European research project MUSIC-haic has been conceived to fill this gap and has started in September 2018.

The present paper deals with the accretion of supercooled large droplets (SLD) at high velocity on wall. A visualization technique of the accretion of ice is used to measure and characterize the thickness of ice during the accretion phenomenon. Influences of air velocity, air temperature, drop size, impact angle and altitude were studied. The experiments are conducted in the ONERA icing wind tunnel, which allows to reach regimes close to realistic conditions for aircrafts (i.e. high velocity: → 190 m/s and altitude: → 11 500 m).

This paper proposes an experimental investigation of fast impinging large droplets in non-icing conditions. Two main aspects of the impact event are analyzed and discussed: the impact dynamics as a function of the surface nature and the deposition rate of the liquid on the impingement surface for various conditions. The data has been recorded and characterized at ambient pressure and a temperature of the air between 5 and 10°C using a vertical wind/droplet tunnel. To avoid the droplets evaporation the relative humidity was controlled. The morphology of impact was studied by backlighted imagery and quantitative results were obtained by image analysis. The deposition rate was obtained weighting the water accumulated on the impingement plate. Examination of splashing events images obtained on a clean surface and on blotter paper shows important differences in terms of secondary drop generation.

Recent aircraft incidents and accidents have highlighted the existence of icing cloud characteristics beyond the actual certification envelope defined by the JAR/FAR Appendix C, which accounts for an icing envelope comprising water droplets up to a diameter of 50 μm. The main concern is the presence of SLD (Supercooled Large Droplets), with droplet diameters well beyond 50 microns. In a previous European-funded project, EURICE, in-flight icing conditions and theoretical studies were performed to demonstrate the existence of SLD and to help characterize SLD clouds. Within the EXTICE project the problem of SLD simulation is addressed with both numerical and experimental tools is being addressed. In this paper the objectives and main achievements of the EXTICE project will be described.

Numerical simulation of ice accretion on aircraft surfaces necessitates a good prediction of wall friction coefficient and wall heat transfer coefficient. After the icing process begins, surface roughness induces a high increase of friction and heat transfer, but simple Reynolds analogy is no longer valid. An experimental campaign is conducted to provide a database for numerical model development in the simple configuration of a heated flat plate under turbulent cold airflow conditions. The flat plate model is placed in the centre of the test section of a wind tunnel. The test model is designed according to constraints for the identification of friction and heat transfer coefficients. It includes three identical resin plates which are moulded to obtain a specified roughness on the upper surface exposed to the flow. Only the 3rd resin plate is heated on its lower face by an electrical heater connected to a temperature regulator.

The Phylog project aims at offering a model-based software-aided certification framework for aeronautical systems based on multi/many-core architectures. Certifying such platforms will entail fulfilling the high level objectives of the MCP-CRI / CAST-32A position paper. Among those, two types of analysis are required: interference and safety analyses. Because of the large size of the platforms and their complexity, those analyses can lead to combinatorial explosion and to some misinterpretation. To tackle these issues, we explore a service-based modelling approach that leads to a simplification of the analyses and to the highlighting of salient properties, making the adaptation of the certification argumentation efficient.