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The flow field generated by the flow into a jet engine air-intake, with near ground effects, is considered. The axial inflow in the neighborhood of the ground generates a system of unsteady vortices. Some of these vortices extend from the air-intake towards the ground. Some of these vortices are strong enough to dislocate and even lift small objects from the ground up to the air-intake. The dynami

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

Wall-bounded turbulent flows are central to a wide range of engineering applications, where surface roughness can significantly influence both frictional drag and convective heat transfer. While the momentum effects of roughness have been significantly advanced in the literature, the thermal counter parts remain insufficiently understood. This study addresses the critical gap in understanding roug

Fundamental characteristics of the reaction-zone structure for CH4-CO2 jets, mimicking a fuel of high CO2 contents such as biogas, burning in a heated coflow on a piloted jet burner have been investigated. Jet flames under diffusion and MILD combustion conditions were studied using planar laser-induced fluorescence (PLIF) of O-atom radicals and CO for different CO2 contents of the fuel jet. Numeri

In this paper, the flame-wall interaction of reacting diesel spray under engine like conditions is investigated using large eddy simulations. The aim of this study is to understand the influence of the distance between the wall and the spray nozzle on the air entrainment rate, which is a key variable in formation/oxidation process of soot. Three experimental cases are investigated, a free jet case

Large eddy simulations are performed for a single- and multiphase jets in crossflow (JICF). The multiphase JICF are compared to the single-phase case for the same momentum and mass flow ratios but with droplets of different sizes. Multiphase JICF have stronger counter-rotating vortex pairs (CVPs) than a corresponding single-phase JICF. Moreover, their trajectories are higher and their induced wake

Klimatförändringarna påverkar vår värld och det behövs ett mer hållbart samhälle. Flygindustrin är i behov av förändring, men flygmotorer är mycket komplexa och tar tid att utveckla. Termoakustiska instabiliteter har kraften att förstöra en motor, men också att minska miljöpåverkan. Samtidigt möjliggör ökad beräkningskraft i moderna datorkluster att detaljerade simuleringar kan utföras för att stuClimate change is affecting our world and a more sustainable society is needed. The aviation industry is in need of change but aero-engines are very complex and take time to develop. Thermoacoustic instabilities have the power to destroy an engine, but also to reduce the environmental impact. At the same time, increasing computational power allows detailed simulations to be executed in order to st