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In-flight icing significantly influences the design of large passenger aircraft. Relevant aspects include sizing of the main aerodynamic surfaces, provision of anti-icing systems, and setting of operational restrictions. Empennages of large passenger aircraft are particularly affected due to the small leading edge radius, and the requirement to generate considerable lift for round out and flare, following an extended period of descent often in icing conditions. This paper describes a CFD-based investigation of the effects of sweep on the aerodynamic performance of a novel forward-swept horizontal stabilizer concept in icing conditions. The concept features an unconventional forward sweep, combined with a high lift leading edge extension (LEX) located within a fuselage induced droplet shadow zone, providing passive protection from icing.

This paper focuses on the design of the thermoelectric ice protection system (IPS) for the engine air intake of the Next Generation Civil Tiltrotor (NGCTR), a demonstrator under development in Leonardo Helicopters. A specific IPS design strategy for the novel intake configuration is proposed. The main constraint which driven the design strategy is a maximum power of 10.6 kW available for the full intake IPS system. The IPS was designed for safe aircraft operations within the Appendix-C icing envelope. The numerical approach adopted to perform the design and the resulting IPS concept are presented. Calculations of the required IPS heat fluxes revealed that maintaining running wet conditions on the entire intake surface is not feasible due to the limitation to the maximum IPS power demand. Therefore, a de-icing IPS design strategy is proposed. The anti-icing mode is adopted only on the lip region to avoid formation of ice caps whereas de-icing zones are defined within the intake duct.

The H2020 funded FITGEN project aims to deliver a fully integrated e-motor-inverter-transmission power unit for next generation electric vehicles. This paper describes the design and optimization of a liquid cooling system for the e-motor. Three variants of a three-dimensional conjugate heat transfer model, based on the Reynolds-averaged Navier-Stokes (RANS) and energy equations, are used to carry out the design process: a CFD model of the liquid cooling system to assess candidate configurations, a CFD and heat transfer model of the full e-motor to calculate heat transfer boundary conditions, and a CFD and heat transfer model of a reduced geometry including liquid cooling system to carry out optimization and sensitivity studies. The design process identifies a promising cooling system configuration made up of axial and circumferential ribs, satisfying requirements for inlet and outlet position, volumetric flow rate, overall pressure drop, manufacturability and maintainability.

This paper aims at providing the scientific community with an overview of the H2020 European project 3beLiEVe and of its early achievements. The project has the objective of delivering the next generation Lithium-Nickel-Manganese-Oxide (LNMO) battery cells, in line with the target performance of the “generation 3b” Li-ion battery technology, as per EU SET-plan Action 7. Its activities are organized in three main pillars: (i) developing the 3b next generation LMNO battery cell, equipped with (ii) an array of internal and external sensors and complemented by (iii) manufacturing and recycling processes at scale. At present, 3beLiEVe is approaching the completion of its first project year (out of a total project planned duration of 42 months). Hence this paper, beyond presenting the overall project’s structure and objectives, focuses on its earliest results in the fields of the cell material formulation, arrangement of sensors and design of the battery pack.

The widespread of hybrid and battery electric vehicles is vital for the future of low-carbon mobility. In this context the delivery of affordable and efficient electric motor technologies together with high energy density storage devices are key aspects to enable the mass market take-off of electrified vehicles. The objective of this paper is to provide the scientific community with the results and design features of an innovative and rare-earth free electric motor technology based on the synchronous reluctance machine concept. This technology is capable to provide sufficient power density and higher driving cycle energy efficiency compared to the current state-of-the-art rare-earth permanent magnet synchronous machines used for automotive applications. The motor is designed to be integrated within a hatchback rear driving axle vehicle, achieving the maximum energy efficiency in urban operational conditions.

In hybrid and electrical vehicles new challenges in meeting the drivers' expectation with regards to acoustic comfort arise. The absence of the internal combustion engine noise enhances the passengers' perception of other noise sources, such as the Heating, Ventilation and Air-Conditioning (HVAC) system. Therefore efficient and reliable numerical models able to predict flow-induced broadband noise have become a major research topic in automotive industry. In this framework, the Zonal LES coupled with the Ffowcs Williams-Hawkings (FWH) acoustic analogy are capable to simulate broadband noise from low speed axial fan. As demonstrated in previous works from the authors, this approach is able to cope with the complexity of the physical phenomena involved (i.e. turbulent noise generation, laminar-to-turbulent transition, etc.), even though the numerical model requires a careful setup of the mesh topology, boundary conditions and simulation parameters.

Low noise design of ventilation systems is an emerging topic in modern vehicle industry, since the thermal and acoustic comfort experienced by the passenger is even more important to define design criteria of HVAC components. Despite of the recent progresses of numerical approaches in the frame of aerodynamic and aeroacoustic simulation, the state of the art in Computational Fluid Dynamics (CFD) and Computational Aeroacoustics (CAA) is still far away to be capable to drive the design of low-noise targeted components. This is mainly due to the high complexity of physical phenomena involved in the noise generation mechanisms, mostly related to flow turbulence usually requiring approaches (e.g. Large Eddy Simulation, LES) with computational demands that cannot be easily afforded for industrial design purposes. The goal of this paper is providing an inexpensive, fast and reliable technique for the aeroacoustic simulation of broadband noise arising from axial fans.