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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

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

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

The objective of this thesis is to numerically simulate a fluid jet injected into a crossflow of the same or another fluid, respectively. Such flows are encountered in many engineering applications in which cooling or mixing plays an important role, e.g. gas turbine combustors. The jet in crossflow (JICF) is used both for cooling and for injecting liquid fuel into the air stream prior to combustio

Five different low-Mach large eddy simulations are compared to the turbulent stratified flame experiments conducted at the Technical University of Darmstadt (TUD). The simulations were contributed by TUD, the Institute for Combustion Technology (ITV) at Aachen, Lund University (LUND), the EM2C laboratory at Ecole Centrale Paris, and the University of Duisburg-Essen (UDE). Combustion is modeled by

Over the last few years, there has been a proliferation of different kinds of movements across the globe as citizens agitate for economic, socio-political and environmental change. In the Democratic Republic of Congo (DRC), where the country has been involved in a series of wars, attention has rather been eschewed towards the rape and sexual violence of women and girls. Using post-colonialism and

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