TurboNoiseBB is a response to the EC-Call ‘Mobility for Growth’, under the topic, ‘Enhancing resource efficiency of aviation’. The research and innovation action is targeted at the reduction of noise at the source. It supports the EC objective of reducing perceived noise by 50% and 65% in the short (ACARE Vision 2020) and long-term (Flightpath 2050) respectively.
The overarching technical objective is the development of concepts and enabling technologies aimed at reducing aeroengine noise at source rather than by affecting sound transmission, for example, by improved liner performance. Fan broadband noise (BBN) is a major aircraft noise challenge. Previous research programmes have shown that it is unlikely to reduce significantly fan broadband noise without improved understanding of the source mechanisms. Advances in computational methods, which have revolutionised tone noise prediction, have yet to make an equivalent impact on broadband noise prediction, due to the difficulty in accurately predicting turbulent flow that is the source of fan broadband noise. TurboNoiseBB will address these issues enabling a major technical leap in providing the industry with low fan broadband noise concepts, based on an improved understanding of the broadband noise source mechanisms and validated broadband noise prediction methods.
The quantitative objective of TurboNoiseBB is to provide a 3 dB reduction at source on fan noise alone. In the process, TurboNoiseBB will advance the current noise technologies to higher TR-levels. The plan is to raise the TRL of innovative low noise OGV concepts from 2-3 up to 4-5 by performing large scale fan rig tests. High fidelity CFD/CAA computations will also advance the state-of-the-art CFD/CAA broadband noise design methods to a higher level to be integrated within industry-exploitable tools. The main TurboNoiseBB technologies as well as their expected advance in TRL level are listed in the table below.