The aim of this work is to improve and compare the performance of pure gasoline ethanol blend and hydrous ethanol blend fuels for spark ignition engine without major fuel system component modification. The comparative experiments were conduct on mechanical gasoline engine fueled with pure gosine, E10 and HE10.The effects of the engine loads and the additions of ethanol and water on combustion and emission characteristics were analyzed deeply. The modified engine was tested with gasoline-ethanol-water blend emulsion as a fuel, and the effect of data were recorded on brake torque, brake power, brake specific fuel consumption, thermal efficiency, exhaust emission (CO, CO2, HC, O2) and smoke emission. In addition to performance test, the study on the miscibility of water, ethanol and gasoline blend was conducted mainly to know what extent water can be added to ethanol gasoline blend without phase separation. The amount of water it can be tolerate in the hydrous alcohol when used as a blending component with gasoline is up to 5% of ethanol. Higher water solubility in ethanol gasoline blends may be obviously useful and suitable nevertheless, temperature continuous ability of water to remain soluble in the blend is significantly affected by temperature and improvement in combustion characteristics. According to the experimental results, compared with pure gasoline and E10 blend, HE10 showed higher peak brake torque at high load. Increases in brake power were observes for HE10 fuel at all the operating conditions. The usage of HE10 fuel at optimum load conditions reduces HC, CO and CO2 emissions significantly. In addition, decreases in NOX emissions were observed for HE10 from 0 Nm to 80 Nm. From the results, it can be concluded that HE10 fuel can be regard as a potential alternative fuel for gasoline engine applications.
