Experiments were conducted on a four-cylinder direct-injection diesel engine with 10% and 20% of the engine load taken up by fumigation ethanol injected into the air intake of each cylinder, to investigate the gaseous, particulate mass (PM) emissions, and number concentration and size distribution of the engine under five engine loads at the maximum torque engine speed of 1800 r/min. The experimental results show that at low engine loads, the brake thermal efficiency (BTE) decreases with increase in fumigation ethanol; but at high engine loads, the BTE is not significantly changed by fumigation ethanol. Fumigation ethanol can effectively decrease in brake specific nitrogen oxides (BSNOx), particulate mass and number emissions but significantly increase in brake specific hydrocarbon (BSHC), brake specific carbon monoxide (BSCO) and proportion of BSNO/BSNO2. Also, the geometrical mean diameter of the particles (GMD) increases with increase in engine load but the diameter is not changed by fumigation ethanol in all cases.
YAO ChunDe1, ZHANG ZhiHui1,2, CHEUNG ChenShun2 & XU GuangLan1 1 State Key Laboratory of Engines, Tianjin University, Tianjin 300072, China
