| Summary: | The concern with the environment led the human being to develop new alternative fuels to reduce pollution and mitigate the emission of greenhouse gases. The air transport sector and the burning of fossil fuels are responsible for a huge portion of the pollution. Therefore, introducing new sustainable ways to provide energy, such as biofuel, is of major importance. However, in order to make these new energy sources more efficient and safer, it is necessary to carry out studies related to the injection of fuel into the combustion chambers, and the impact of droplets. This study focuses on an experimental investigation of a single droplet impact onto a heated solid surface. The main purpose of this work is to analyse the influence of wall temperature on the impact morphology of a single droplet and observe the possible outcomes. To do so, in these experimental tests, Jet Fuel and HVO (Hydroprocessed Vegetable Oil) mixtures were used. The fluids tested were: water (as a control group), 100% Jet A-1, 75% Jet A-1 and 25% NExBTL, 50% Jet A-1 and 50% NExBTL, and 100% NExBTL. The present work studies the impact outcomes depending on the working fluids and the wall temperature. The impact energy was kept constant. Therefore, the Weber number in this experiment was set to W e = 320 by varying the droplet diameter or the impact velocity. Furthermore, different wall temperatures were chosen, that vary from Tw = 25ºC to Tw = 330ºC, to seek for every possible impact phenomenon and characterise the impact morphology. The impact dynamics were captured using a high-speed digital camera and the images were digitally processed. It was possible to observe the heat regimes for all fluids, as well as two additional regimes for the mixtures of 75% jet fuel - 25% HVO and 50% jet fuel - 50% HVO.
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