四行程機車引擎使用酒精汽油燃料對其性能及排放空氣污染物之影響

Abstract

本研究以不同比例酒精汽油使用單缸四行程125 cc引擎，在不變動化油器結構下，針對引擎性能及空氣污染物排放之影響進行探討。以E0、E10、E20、E30、E40五種濃度之酒精汽油於30、40、50、60 km/hr四種定速下來進行實驗。測量項目包括動力輸出、耗油量、氣狀污染物及粒狀污染物之排放濃度，並分析其結果。結果顯示，於汽油中添加酒精會導致引擎動力輸出有些許下降而耗油量略增，動力輸出平均減少了0.83 ~ 30.82 %，制動燃油消耗率增加了7.02 ~ 30.79 %。在空氣污染物排放的影響上，CO的排放量隨著酒精的加入有73 ~ 98.47 %之降幅。而氮氧化物之排放濃度亦隨著酒精的添加比例增加有增加的趨勢，平均增幅約在9.46 ~ 63.55 %不等。粒狀污染物則隨著混合燃料中酒精的濃度增加而有減少的趨勢，平均總個數濃度約減少7.62 ~ 90.6 %，平均總重量濃度則是降低了21.76 ~ 99 %。

The effects of air pollutant emissions and engine performance of a single four-stroke 125 cm3 displacement motorcycle engine with it’s original carburetor using various ethanol-gasoline blended fuels were investigated in this study. The experiments were conducted at four speeds (30, 40, 50, and 60 km/hr) with five kinds of ethanol blending percentage (0, 10, 20, 30, and 40% v/v) fuel conditions. Power output, fuel consumption, gaseous air pollutants, and aerosol air pollutants were measured to analyze their results. The results showed the power output was slightly decreased and the fuel consumption was a little increased when ethanol-gasoline blended fuel was used. The results showed an average reduction of 0.83 - 30.82 % in engine power output and an average increase of 7.02 - 30.79 % in engine brake specific fuel consumption. Regarding the influences of air pollutants compared with using no-ethanol gasoline fuel, the emission of CO had an average reduction of 73 - 98.47 % and the emission of NOx had an average increase of 9.46 - 63.55 %. Furthermore, the particulate matters number concentrations was reduced when the ethanol blended rate was increased, the average total number concentration reduced at 7.62 - 90.6 % and the average mass concentration reduced at 21.76 - 99 %.