【摘要】 在单缸发动机上进行了二甲醚/甲醇均质压燃(HCCI)的试验研究。结果表明,采用二甲醚/甲醇双燃料方式,HCCI的工况范围大幅拓宽,低转速平均指示压力接近0.8MPa。低负荷工况指示热效率随甲醇浓度的降低而升高;对于较高负荷,存在一个指示热效率较高的甲醇浓度区间。正常燃烧范围内,NOx排放一般低于20×10 6,即使在接近爆燃的工况,试验中测得的NOx排放也低于100×10 6;HC和CO排放明显高于柴油机。随甲醇浓度降低,HC和CO排放降低,NOx排放略有升高。更多还原

【Abstract】 Experimental study on HCCI operation fueled with dimethyl ether/methanol was carried out on a single cylinder engine. The results indicate that operating region of HCCI combustion can be largely extended by fueling DME and methanol in dual fuel mode. At low engine speed, the indicated mean effective pressure (p_IMEP) almost reaches 0.8 MPa. At low engine loads, the indicated thermal efficiency increases with the decrease methanol fraction. While at high loads, there exists a region of methanol concentrations for getting optimum thermal efficiency. Under normal HCCI combustion, NO_x emissions are less than 20×10^-6, and even near the knocking limit, the measured NO_x emissions are controlled less than 100×10^-6. Nevertheless, HC and CO emissions give higher value than those of diesel engines. With the decrease of methanol fraction, HC and CO emissions decrease, accompanying with a slight increase in NO_x emissions.更多还原