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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

Temperature stratification plays an important role in HCCI combustion. The onsets of auto-ignition and combustion duration are sensitive to the temperature field in the engine cylinder. Numerical simulations of HCCI engine combustion are affected by the use of wall boundary conditions, especially the temperature condition at the cylinder and piston walls. This paper reports on numerical studies an

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

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

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

DLE (Dry Low Emission) techniques are widely used today to reduce the harmful NOx emissions associated with high combustion temperatures. In many DLE systems the fuel and air are premixed which effectively keep the flame temperature as low as possible, ideally equal to the turbine inlet temperature. By using premixing stability issues such as flash back and combustion driven dynamics may occur. Op

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

Numerisk strömningsmekanik är en kraftfull metod för att förstå flödet och förbränningen som sker i flygplansmotorer och kommer att vara ett avgörande verktyg i övergången från konventionella fossila bränslen till hållbara alternativ. Eftersom mer forskning har skett kring konventionella bränslen bör en simuleringsmetod för alternativa bränslen föregås av en metod som verklighetstroget kan simulerComputational fluid dynamics is a powerful method for understanding the flow and combustion that occurs inside aircraft engines and will be a key tool in the transition from conventional fossil-based fuel to sustainable alternatives. Because conventional fuels have been more widely researched, an attempt at simulating the combustion of alternative fuels should be preceded by the development of a m