ICR leads the European Clean2Sky PIANO Project
The Clean Sky 2 initiative of the European Commission’s H2020 programme has as one of its fundamental pillars the support for the development of the “New Generation Civil Tilt Rotor (NGCTR)” prototype to meet the needs of the commercial aviation sector in the operating segment between routes operated by transport helicopters and regional commercial aircraft. One of the main problems identified in this type of aircraft is the lack of interior acoustic comfort in the passenger cabin.
In this context, ICR proposes the European-wide project PIANO (Path Identification for Active Noise Control), in which it acts as Project Coordinator, and which aims to bring together Advanced Transfer Path Analysis (ATPA) and Active Noise Control (ANC) technologies, with the support of important partners in the ANC sector, such as the French Technofirst and the DSL laboratory of the National University of Athens (NTUA). ICR brings its experience in project management in industrial vibroacoustics and its own technology of transmission path analysis (ATPA).
Usually, to predict and characterize the noise and vibration transmission paths of a system and to obtain predictions of the interior noise levels, simulation models based on SEA (Statistical Energy Analysis) are performed. This method is strongly dependent on the input parameters so a thorough knowledge of the vibro-acoustic characteristics of the system is key. The ATPA method emerges as a powerful tool for understanding these characteristics.
In this project we intend to use the ATPA methodology to obtain the coupling parameters between the different subsystems in the SEA models. The ATPA method, which starts from a definition of the study system as a set of subsystems, allows obtaining the vibro-acoustic connectivities and the SEA coupling factors between them.
The second major objective of this project is the mitigation of both tonal and broadband noise by means of innovative active noise control techniques. These two noise sources usually come from the rotating operation of propeller blades and from the aeroacoustic sources produced by the turbulent boundary layer in flight conditions. Noise control techniques using ANC systems provide benefits that classical isolation and absorption solutions do not provide, such as the attenuation of low frequency noise using global ANC approaches and the mitigation of tonal noise using local ANC concepts, such as personal noise comfort bubbles.
This second thematic block of the proposed innovative project will allow to study how to achieve a reduction of the noise in the cabin, considering the restrictive requirements of weight of the aircraft at a reasonable cost. The final results will provide a complete definition of the architecture of the ANC systems on board the aircraft, as well as the components that must be installed to mitigate noise in operation. These systems can act directly on the components that, using the ATPA method, are identified as the most critical in the transmission of noise to the passenger cabin.