Study of fuel consumption when introducing DME or ethanol into diesel engine

An investigation of the effect of DME or ethanol on fuel consumption is conducted in a four-stroke, one-cylinder, direct-injection diesel engine. DME or ethanol is first heated to pyrolyze and then the resultant product gas is introduced into air intake. Brake Specific Fuel Consumption (BSFC) can be reduced a lot, when emulsified fuel (diesel fuel emulsified with water) is fueled to diesel engine and DME is heated to about 1000 K before its being introduced into air intake. Results show that BSFC can be decreased by about 10% and diesel fuel consumption can be decreased by 18%. High saving rate of BSFC up to 10% is also acquired using ethanol instead of DME. To achieve high saving rate of BSFC, the heating temperature of about 1000 K is needed for DME operation, while the diesel engine exhaust temperature of about 750 K is enough for pyrolyzing ethanol. Hydrogen produced in DME or ethanol pyrolysis is considered as the main reason for the excellent fuel saving. The technique adopted in the present work is extremely easy to utilize, and may be firstly adopted on diesel engines for power plants, trains, ships, etc.