OPTICAL INVESTIGATION OF SPRAY CHARACTERISTICS FOR LIGHT FUEL OIL, KEROSENE, HEXANE, METHANOL, AND PROPANE

The present study investigated liquid fuel spray penetration and opening angles for EN 590 light fuel oil (LFO), kerosene, hexane, methanol, and propane. Moreover, droplet sizes were studied for methanol and light fuel oil sprays from a single location at the edge of the sprays. The fuels were injected from a marine-size common rail diesel injector into a constant volume spray chamber with nitrogen atmosphere, and the results were based on shadow image analysis. The results indicated that propane sprays would penetrate slower and less than the sprays of the other fuels, but the differences seemed to decrease when increasing chamber density. With the exception of the lowest tested chamber density of 1.2 kg/m(3), propane formed significantly narrower liquid sprays than the other fuels. Apart from propane, the fuels had mostly similar responses to increased chamber densities. Variations between repetitions were large in comparison to the differences between the liquid fuels. Concerning droplet size measurements, the results suggested that methanol sprays would contain slightly smaller droplets than LFO sprays in the tested conditions. This finding agrees with an earlier study, albeit the found differences were considerably smaller.