抄録
We experimentally evaluate a performance and exhaust emissions of a four stroke direct injection diesel engine operating on water-fuel emulsions. Four types of water emulsified fuels of diesel fuel and biomass based fuels are produced after the suitable selection of emulsifier. The ratio of water to fuel oil was changed by volume from 0 to 30%. We use JIS # 2 diesel fuel, diesel fuel containing 50% volume waste food-oil (Blend 50), waste food-oil containing 50% volume polystyrene pylolysis oil (Blend PS),and soybean oil methyl ester (VDF) as tested fuels. The combustion characteristics and emissions such as NOx, CO, HC, HCHO, O_2, CO_2 and smoke, particle size distribution are compared with the case of diesel fuel. We found that (i)the CO emissions of water-emulsified fuels are higher than diesel fuel especially in the low load range. (ii)the NOx emissions of water-emulsified fuels are lower than diesel fuel in the almost load range, and smoke, PM emissions of water-emulsified fuels are lower than diesel fuel, (iii)fuel consumptions of engine operating on water-emulsified fuels are lower than original fuel in the whole engine operating range.
