SILENCE (R)
This is a European Union program dedicated to the reduction of aircraft noise. Its objective is the large-scale experimental validation of noise reduction technologies concerning the engine (aeroacoustic design, active technologies), the nacelle (aeroacoustic design, innovative acoustic treatment, active noise control, chevron type nozzles, air inlet), and aircraft (aeroacoustic design). The program groups over 50 companies (including Airbus Industrie, Rolls-Royce, MTU Aero Engines and Snecma), along with research centers and universities. Silence(R) will also evaluate the acoustic performance of typical future-generation engines, such as those studied within the scope of the EEFAE program, including CLEAN (see below).
CLEAN
“CLEAN” is one of the two test platforms in the European Commission’s Efficient and Environmentally Friendly Aero Engine (EEFAE) program (5th PCRD). Enjoying financial support from the EU, it aims to reduce polluting emissions and fuel consumption on civil aircraft, in particular cutting carbon dioxide by about 20% and oxides of nitrogen (NOx) by some 80% in relation to current engines.
MTU Aero Engines is program manager, and is also in charge of the high-speed low-pressure turbine and the heat exchanger. Snecma has technology leadership and is responsible for the gas generator, while Volvo Aero in contributing to the casings and final assembly. Avio is working with Snecma to manufacture and test the combustor.
CLEAN technology demonstration testing started on September 29, 2004 at the University of Stuttgart, and recently came to a successful conclusion in a simulated altitude chamber.
In particular, the CLEAN demonstrator tested two new technologies developed by Snecma: a combustor based on LPP (lean prevaporized premixed) technology, built in conjunction with Avio; and the active surge control device (CAP). The latter technology is unprecedented, since no device of this type had previously operated from idle to full throttle on a modern engine, using a highly-loaded high-pressure compressor as on the CLEAN demonstrator.
NEWAC - New Aero-engine Core concept
NEWAC (New Aero Engine Core Concepts) is a new European technology program launched in May 2006. This new research program is backed by the EU under its 6th Research Framework Program and commands an overall budget of 71 million euros. NEWAC will run for four years under the lead of MTU Aero Engines and aims to reduce CO2 emissions by 6 per cent and NOx emissions by 17 per cent through improvements to the engine core.
40 different partners including Snecma, Rolls-Royce and Avio among the major players are jointly developing intelligent compressors, improving the combustor and integrating heat exchangers. The approach is to identify the potentials of the new technologies and bring the most promising among them to maturity.
In the 20 years ahead, air traffic is predicted to grow by about five percent per year. Emerging innovative core engines like the Active Core, Intercooled Core, Flow Controlled Core and Intercooled Recuperative Core will be able to appreciably reduce emissions and fuel consumption. In the course of the program new components for these core engines will be built and tested.
NEWAC draws on the lessons learned from the now-complete CLEAN and Antle programs. It also complements VITAL, led by Snecma under the EU’s 6th Research Framework Program, which attempts to optimize the engine’s low-pressure components. The findings of VITAL and NEWAC together will provide the European engine industry with a complete inventory of available and meaningful technologies to use in the development of future engines.