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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.

This paper presents a work carried out within the FULMEN lightning-on-aircraft oriented European project. It is the second part of the general presentation on the analysis of EM environment inside the aircraft. Therefore, it focuses on numerical calculations of voltage and current transfer functions on the ports of the same prototype wiring harness installed in several aircraft structures. The calculations have been carried out with the cable network CRIPTE code and rely on 3D field calculations performed by Ericsson Saab Avionics. The link between the cable code and the 3D code is achieved through the component of the incident electric field tangent to the running path of the wiring.

Model Based Safety techniques have been developed for a number of years, though the models have not been customised to help address the safety considerations/ actions at each refinement level. The work performed in the MISSA Project looked at defining the content of “safety models” for each of the refinement levels. A modelling approach has been defined that provides support for the initial functional hazard analysis, then for the systems architectural definition level and finally for the systems implementation level. The Aircraft functional model is used to apportion qualitative and quantitative requirements, the systems architectural level is used to perform a preliminary systems safety analysis to demonstrate that a system architecture can satisfy qualitative and quantitative requirements.

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.

Critical control systems are often built as a combination of a control core with safety mechanisms allowing to recover from failures. For example a PID controller used with triplicated inputs. Typically those systems would be designed at the model level in a synchronous language like Lustre or Simulink, and their code automatically generated from those models. In previous SAE symposium, we addressed the formal analysis of such systems - focusing on the safety parts - using a combination of formal techniques, ie. k-induction and abstract interpretation. The approach developed here extends the analysis of the system to the control core. We present a new analysis framework combining the analysis of open-loop stable controller with those safety constructs. We introduce the basic analysis approaches: abstract interpretation synthesizing quadratic invariants and backward analysis based on quantifier elimination.

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.

This paper describes the microaccelerometer ASTRE, developed as Laboratory Support Equipment of Columbus, to monitor the residual microgravity disturbance level in the very low frequency range. ASTRE will be integrated in the already flown Microgravity Measurement Assembly (MMA). The paper recalls the microgravity environment which is required on-board Columbus and shortly describes expected discrepancies between the requirements and the predicted, more noisy, situation.

This paper describes the new analysis software for the contamination modelling and outgassing / vent analysis, which has been developed under ESTEC contract by HTS and ONERA. A major part of the software enhancements have been dedicated to the improvement of the algorithms describing the physical processes involved in outgassing and contamination of species in orbit conditions. However, this paper concentrates on additional aspects of the new software tool, which are of interest for space environment analysis software development in general and the thermal analysis community in particular: The use of commercial software packages for the generation of the discrete model geometry and result visualisation. The interfacing possibilities of the software tool with thermal analysis tools.