SI引擎富氧冷起動效益

Oxygen-enriched Cold Start of a SI Engine

陳榮洪(Rong-Horng Chen) ； 蕭瑞陽(Jui-Yang Hsiao) ； 紀偉民(Wei-Min Ji)

《燃燒季刊》 91期 (2015/11) Pp. 83-94

https://doi.org/10.30041/CQ.201511_(91).0007

摘要

富氧冷車起動能提高燃燒溫度，有效縮短三元觸媒轉換器預熱時間，亦可減少因較濃的混合比而燃燒不完全所產生HC和CO的排放濃度。本研究比較不同氧濃度進氣空氣之SI引擎富氧冷車起動效益。實驗控制富氧空氣為27±0.3°C，引擎本體溫度及冷卻水溫皆為25±0.3°C。實驗顯示隨進氣含氧濃度愈高，其CO、HC排放濃度愈小，NO則隨進氣含氧濃度愈高排放濃度愈大量增加。起動後150sec內，含氧25%進氣條件下明顯抑制CO、HC排放濃度且含氧感知器尚未作動。含氧30%進氣條件之排氣中O_2排放濃度過高，混合氣過稀回饋訊號干擾ECU的噴射率控制，就整體效益而言效益不佳。

關鍵字

冷車起動 ； 富氧進氣 ； SI引擎 ； 乙醇－汽油

並列摘要

Oxygen-enriched cold start can increase the combustion temperature, shorten the warm-up time of the three-element catalytic converter and can also reduce the emission concentration of HC and CO which cause by the incompletely combustion due to a richer mixture ratio. This study investigated the oxygen-enriched SI engine cold start efficiency with different oxygen concentration. For different intake air oxygen concentration, the enriched air was controlled at 27±0.3°C, the engine coolant temperature and the body temperature are all controlled at 25±0.3°C. Experimental results show that a higher intake oxygen concentration induces a lower emission concentration of CO and HC, and a higheremission concentration of NO. Within 150sec after starting, under the condition of 25% oxygen intake ratio, the inhibitions of CO and HC emission concentration are more obviously and the O_2 sensor has not been actuated. Under the condition of 30% oxygen intake ratio, the emission concentration O_2 within the exhaust is too high; the mixture is too lean then the feedback signal interferences the injection control of ECU and induces a poor overall efficiency.

並列關鍵字

cold start ； oxygen-enriched air ； SI engine ； ethanol-gasoline