Turbomachinery noise radiation through the engine exhaust
TURNEX has delivered validated industry-exploitable methods for predicting turbomachinery noise radiation through exhaust nozzles, which will allow EU industry to compete effectively with NASA-funded technology developments in the US. It has also delivered a technical assessment on the way forward for European fan noise testing facilities and an assessment of exhaust nozzle concepts for noise reduction at source.
TURNEX has addressed technical domain 2.f (External noise) of area 2 (Improving environmental impact with regard to emissions and noise) for Priority Thematic Area 4 (Aeronautics and Space) of the Specific Programme ‘Integrating and strengthening the European Research Area’. It supports the EU FP6 objective of reducing aircraft external noise by 4-5 dB and by 10 dB per operation in the short and long-term respectively
Research is needed to develop innovative concepts and enabling technologies to reduce aero engine noise at source. Turbomachinery noise radiating from the bypass and core nozzles is becoming a dominant noise source on modern aircraft, but, while recent EU research programmes have made significant progress in reducing both the generation of turbomachinery noise and the radiation of noise from the intake, little work has been conducted on reducing the radiation of turbomachinery noise from exhaust nozzles. TURNEX has addressed this shortfall by delivering improved understanding and validated design methods, and by evaluating a number of low-noise exhaust nozzle configurations aimed at a source noise reduction of 2-3dB.
The goal of TURNEX was to develop concepts and enabling technologies for reduction of engine noise at the source, through an improved understanding, modelling and prediction of fan and turbine noise radiation from exhaust nozzles, and through the evaluation of a number of low-noise exhaust nozzle configurations. To achieve that goal, TURNEX had four focussed, ambitious objectives.
The consortium consisted of two leading airframe manufacturers, three leading engine manufacturers, an SME that specialises in computational aeroacoustics software, three leading research centres and three leading universities from France, Germany, Belgium, the Netherlands, Italy, Turkey and the UK. This mix of partners has formed the basis for delivering the ambitious project objectives.