Das Projekt "Technologies enhancement for clean combustion in aero-engines (TECC-AE)" wird vom Umweltbundesamt gefördert und von Rolls-Royce Deutschland Ltd & Co KG durchgeführt. Due to continuous efforts through past and ongoing European projects, lean combustion by means of internally staged injectors now appears to be the promising technology for obtaining the required emission reductions compatible with a sustainable growth of aviation transport. (cf ACARE 2020). Recognising that putting into service such a technology as soon as possible is the only way to effectively reduce the aviation environmental impact, TECC-AE addresses some unavoidable issues in order to: - Solve the main limitations identified during past and ongoing projects appearing when lean combustion is pushed toward its maximum potential about NOx emissions reduction. In particular, TECC-AE will a) Provide full combustor operability in terms of ignition, altitude relight and weak extinction performance b) Suppress the occurrence of thermo-acoustic instabilities by reducing the combustor sensitivity to unsteady features to a level such instabilities will not happen - Ensure injection system robustness with respect to coking that can appears during transient operations of the engine. - Optimise the combustion system s operational and environmental performance through all the flight phases - Develop, demonstrate and validate design rules, CFD capabilities and scaling laws. Prime Contractor: SNECMA SA; Paris; France.
Das Projekt "Knowledge for ignition, acoustics and instabilities (KIAI)" wird vom Umweltbundesamt gefördert und von Rolls-Royce Deutschland Ltd & Co KG durchgeführt. For the time being, the European engine industry does not have at its disposal methodologies adapted to predict the unsteady behaviour of low NOx combustors. Consequently and in order to be able to set up the development of low NOx technologies, KIAI will deliver reliable unstationary CFD tools which will allow a deep comprehension of unsteady phenomena. The main objective of the KIAI project is to provide reliable methodologies to predict the stability of industrial low NOx combustors, as well as their ignition process from spark to annular combustion. When used at an early stage in the conception cycle of low NOx combustors, KIAI CFD methodologies will play a key role and considerably accelerate the delivery process of lean combustion technology with a proven capability to reach the 80Prozent NOx emissions reduction required for introduction into service before 2020 with the necessary reliability, safety and economical viability. As already demonstrated by past and ongoing studies and European projects, low NOx technologies lead to crucial unsteady phenomena that are neither controlled nor predictable at the moment. The scientific objectives of KIAI are directly linked to a better understanding and prediction of these unsteady phenomena: - Predict the coupling between the acoustics and the flame - Determine the acoustic boundary conditions of multiperforated plates surrounding the combustion chamber - Account for non-premixed spray flows in the combustion process - Explore aerodynamic unsteadiness in strutted pre-diffusers adapted to high mass flow injectors and develop a liquid film break-up model for an injector - Evaluate the sensitivity of LES predictions to small technological variations of geometry. Prime Contractor: SNECMA MOTEURS SA; Paris; France.