We present different simulations of primary atomization using an adaptive Volumeof-Fluid method based on octree meshes. The use of accurate numerical schemes for mesh adaptation, Volume-of-Fluid advection and balanced force surface tension calculation implemented in Gerris, the code used to perform the simulations included in this work, has made possible to carry out accurate simulations with characteristic scales spreading over several orders of magnitude. The code is validated by comparisons with the temporal linear theory for moderate density and viscosity ratios, which basically corresponds to atomization processes in high pressure chambers. In order to show the potential of the code in different scenarios related to atomization, preliminary results are shown in relation with the study of the two-dimensional and 3D temporal and spatial problem, the influence of the injector and the vortex generated inside the chamber, and the effect of swirling at high Reynolds numbers.

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Droplet impact on a dry solid surface is investigated experimentally. A small obstacle made by layers of adhesive tape is located on the solid surface at some distance from the impact centre. The splashing of the drop starts at the tape, as a sheet of liquid shoots upwards. Angle, speed and dynamics of this liquid sheet are investigated as a function of the distance from the impact centre to the obstacle and its height. Reynolds and Weber numbers are kept constant. Volume-of-fluid simulations reproduce the experiments qualitatively. Measured sheet angles are compared with the predictions of a simple theory.

7Ignition delay times of ethanol/DME/air mixtures were measured in a rapid compression machine and in two high-8 pressure shock tubes at conditions relevant to internal combustion engines. The influences of these conditions on the 9 auto-ignition behavior of the mixture blends were systematically investigated. Our results indicate that, in the low 10 temperature range (650 -950 K), increasing the amount of DME in the fuel mixture increases. At higher 11 temperatures, reactivity is controlled by ethanol and there is almost no visible impact of the fuel mixture 12 composition, whereas DME shows a slower reactivity. The experimental measurements were simulated using an 13 updated mechanism for ethanol which includes the latest experimental or theoretical work in the literature. Results 14indicates that the model is in satisfactory agreement with all of the mixtures. 15 16

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High pressure oxidation of 3-pentanol is investigated in a jet-stirred reactor and in a shock tube.Experiments in the reactor were carried out at 10 atm, between 730-1180 K, for equivalence ratios of 0.35, 0.5, 1, 2, 4 and 1000 ppm fuel, at a constant residence time of 0.7s. Reactant, product and intermediate species mole fractions were recorded using Fourier transform infrared spectroscopy (FTIR) and gas chromatography (GC). Ignition delay times were measured for 3-pentanol/O2 mixtures in argon in a shock tube at 20 and 40 bar, in a temperature range of 1000-1470 K and for equivalence ratios of 0.5, 1 and 2. The fuel did not show any low-temperature reactivity under these conditions in neither experimental set-up and produced various aldehydes and ketones as well as the olefin 2-pentene as intermediates. A kinetic sub-mechanism is developed in order to represent the present data and analyze the reaction pathways.

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