Search Results

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 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.