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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

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

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

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

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

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

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

Anton Nilsson (1887–1989) is one of the most famous people in the Swedish labour movement and a prominent activist with the status of an icon. He was a member of the Young Socialist movement in the working-class city of Malmö, he placed a bomb on the ship Amalthea, which housed 73 English strike breakers, in connection with an extensive dock worker conflict in the Swedish ports. Anton Nilsson was

Strata compiles 37 conversations with artists whose work has made a significant contribution to the Italian and international art scene since 2000. This book is the personal account of a number of encounters, friendships, and professional relationships that Vincenzo de Bellis and Alessandro Rabottini have nurtured over the past twenty years. The conversations explore pivotal moments in each artist

While the eddy covariance (EC) technique is a well-established method for measuring water fluxes (i.e., evaporation or 'evapotranspiration’, ET), the measurement is susceptible to many uncertainties. One such issue is the potential underestimation of ET when relative humidity (RH) is high (>70%), due to low-pass filtering with some EC systems. Yet, this underestimation for different types of EC sy

Abstract in FrenchDepuis longtemps, les anthropologues sont fascinés par les adaptations similaires et les différences intrigantes des cultures circumpolaires. Ces tendances ont été cartographiées, étudiées et interprétées sous différents angles, souvent à des niveaux sociaux ou spatiotemporels différents. Même si ces études ont produit d’importantes quantités de données, celles-ci ne couvrent pasAnthropologists have long been fascinated by the strikingly similar adaptations of circumpolar cultures as well as their puzzling differences. These patterns of diversity have been mapped, studied, and interpreted from many perspectives and often at different social and spatiotemporal scales. While this work has generated vast archives of legacy data, it has also left behind a fragmented understan

Background More than one in five patients who undergo treatment for breast cancer will develop breast cancer-related lymphedema (BCRL). BCRL can occur as a result of breast cancer surgery and/or radiation therapy. BCRL can negatively impact comfort, function, and quality of life (QoL). Manual lymphatic drainage (MLD), a type of hands-on therapy, is frequently used for BCRL and often as part of com