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Abstract in FrenchRésumé : Direkt Profil est un analyseur automatique de textes écrits en français comme langue étrangère. Son but est de produire une évaluation du stade de langue des élèves sous la forme d’un profil d’apprenant. Direkt Profil réalise une analyse des phrases fondée sur desitinéraires d’acquisition, i.e. des phénomènes syntaxiques locaux liés à un développement dans l’apprentissag

The Siemens gas turbine SGT-800 is the largest industrial gas turbine produced by Siemens Industrial Turbomachinery (SIT) offering a dry low emission (DLE) capability below 15 ppm NOx. It has a very high reliability using an annular combustor system with passive damping and 30 DLE burners. To obtain a greater understanding of the mixing process and the flame dynamics and in order to further reduce

Increasing noise regulations at urban airports force jet engine manufactures to develop and build more quiet engines. Over recent years, a significant reduction in fan and mechanical noise has been achieved. However, the jet exhaust is the principal source of noise. The acoustical field that is generated by a turboengine jet exhaust running near the ground level is considered. The full equations o

In this study we describe combustion simulations of a single sector and a fully annular generic multi-burner aero-engine combustor. The objectives are to facilitate the understanding of the flow, mixing and combustion processes to help improve the combustor design and the design process, as well as to show that it is now feasible to perform high-fidelity reacting flow simulations of full annular g

For environmental and human health reasons, the regulations on the emissions from combustion devices are getting more and more strict. In particular, it is important to abate the emission of pollutants deriving from combustion in gas turbines. A solution is the use of swirl stabilized, lean premixed combustion. Besides the beneficial effects, there are still some issues related to instabilities an

Modeling and understanding the vortex breakdown is a key issue of modern Lean Premixed Combustors. The main difficulty of the problem is the unsteady behavior of this type of flow: Large structures resulting from vortex breakdown and the swirling shear-layers, affect directly the flame stabilization leading to heat-release fluctuations and combustion instabilities. Consequently, one needs to captu

The growth of social science and sociology during modernity has always been characterized by a will to create predictability for human actions, under the modern conditions of liberty seen as contingent, unpredictable and unstable. To gain systematic knowledge became a way to solve, counteract or radicalize tensions in society, and thus outweighing the risks of contingency. Furthermore, this develo