舶用4ストロークディーゼル機関の排気特性と性能に及ぼす乳化燃料油中の水粒子径の影響

抄録

Using emulsified fuel, with water particles dispersed in the continuous phase of fuel, is effective in suppressing the emission of polluting matter from spray combustors, such as diesel engines and boilers. This paper discusses the emission characteristics and the performance of a marine four-stroke diesel engine operated with emulsified fuels having different water particle diameters. The research especially focused on how the PM (Particulate Matter) and NO_x (Nitrogen Oxide) emission was affected by the water particle diameter in emulsified fuel.
In the engine experiment, we used Marine Diesel Fuel (MDF) in three emulsified fuels having mean water particle diameters of 3.94μm, 7.71μm, and 8.78μm. The following results were found:
1. In comparison with using MDF, the emission level was decreased by about 10% to 40% by using emulsified fuels, and the smaller the mean water particle diameter of the emulsified fuel, the lower the NO_xemission level.
2. The PM, SOF (Soluble Organic Fraction), and ISF (Insoluble Organic Fraction) emission rates increased with use of emulsified fuel, especially in the low load area.
3. The SFC (Specific Fuel Consumption) of emulsified fuel having the largest mean water particle diameter in this experiment was lower than that of the MDF. Among the three emulsified fuels, the smaller the mean water particle diameter, the higher the SFC.