機車引擎冷起動暫態行車過程污染改善研究

The Improvement of the Exhaust Emissions on a Motorcycle Engine in Transient Cold-Start Conditions

洪榮芳(R.F. Horng) ； 周煥銘(H.M. Chou) ； 吳澤松(T.S. Wu) ； 吳向震(S.C.Wu) ； 蘇粲哲(T.C. Su) ； 何柏村(P.T.Ho) ； 黃國原(K.Y. Huang)

《石油季刊》 39卷3期 (2003/09) Pp. 13-22

https://doi.org/10.30128/JP.200309.0002

摘要

本文主要針對機車引擎冷起動行車暫態過程的污染排放及改善進行探討。改變的參數包括引擎進氣預熱溫度及冷車增濃油量等；量測項目包括引擎進氣溫度、火星塞座溫度、進氣管負壓及污染等，目的在於探討引擎冷車起動過程中引擎的運轉與污染排放特性等。　
冷起動暫態過程包括冷車起步加速、定速行駛及減速等過程。引擎進氣預熱溫度範圍包括室溫（進氣未預熱）、50°Ｃ及70°Ｃ等；引擎起動時增濃油量則由自動阻風器的預先通電時間來加以控制，預通電時間包括0秒、20秒及40秒等。　本研究全部行車過程的實驗均於車體動力計上進行測試。由實驗測試結果得知，在冷起動的暫態行車過程中，CO及HC污染排放均隨著自動阻風器通電時間的增長而逐漸降低。另外亦獲知，HC的排放濃度與進氣負壓有著密切的關係，在車子減速階段進氣負壓越高，HC的排放濃度就越高。

關鍵字

機車引擎 ； 冷起動行車 ； 進氣溫度 ； 污染排放 ； 進氣管負壓

並列摘要

The exhaust emissions from a four-stroke engine in the transient cold-start conditions were investigated in this study. The intake temperatures and the amount of fuel enrichment were the controlled parameters, and the measured items included intake temperatures, spark plug washer temperatures, intake manifold pressures, and exhaust emissions. The objective was to investigate the features of exhaust emissions during the cold start conditions. The strategy for improving the cold-start emissions was to be obtained.
The transient cold-start conditions include the acceleration, cruise driving and deceleration. During the cold-start stage, the engine has not reached the stable temperature. The engine is, therefore, not achieved a steady condition.
In this study, the intake temperatures of the engine were varied from room temperature, 50°C to 70°C. The enrichment of the fuel amount for engine cold start was changed by autochoke valve closing time by controlling the key-on duration of the switch before starting the engine.
The results show that CO and HC emissions decrease with decreasing key-on duration, and the relation between HC emissions and Intake Manifold Absolute Pressure (MAP) is obvious. The higher MAP induces to the higher HC emissions.

並列關鍵字

Motorcycle engine ； Cold start ； Intake temperature ； Exhaust emission ； Intake manifold absolute pressure (MAP)