四行程機車引擎排放粒狀污染物特徵之研究

Characterization of Particles Exhausted from a 4-stroke Motorcycle Engine

許翔璽(Hsiang-Hsi Hsu)

指導教授 ： 林文印

國立臺北科技大學/工程學院/環境規劃與管理研究所/碩士(2006年)

https://doi.org/10.6841/NTUT.2006.00278

摘要

機車為目前台灣地區最普遍的私人交通工具，但是因單位面積機車數量太多，使其在都市環境走走停停的車況下，所產生的各種空氣污染物，對人體及環境造成了相當大的危害。至2005年12月底，機動車輛總數為1,986萬輛，約為1995年總數（1,320萬輛）的1.5倍；而機動車輛中以機車最多，約為1,316萬輛（2005年12月底），占機動車輛總數的66.5％。目前較少研究針對於機車引擎排放污染物，而有關引擎廢氣排放之研究多著重於探討引擎轉速。
本研究試利用四行程機車引擎、引擎動力計、Electrical Low-Pressure Impactor (ELPI)、Micro-Orifice Uniform Deposit Impactor (MOUDI)、Nano Micro-Orifice Uniform Deposit Impactor (Nano-MOUDI)等，建立機車引擎排放微粒採樣系統。以市售之92、95鉛汽油為燃料進行微粒採樣，並使用離子層析儀(Ion Chromatography, IC)及元素分析儀(Element Analyzer, EA)等，分析不同操作條件對於機車引擎排放微粒特徵之影響。
研究結果顯示引擎排放微粒數目濃度隨著轉速的增加而減少、隨著扭力及大氣溫度的增加而增加。以92無鉛汽油當燃料，排放微粒數目濃度於惰轉時為5.6×1010 #/cm3，高轉速時為1.1×1010 #/cm3，扭力2.0 Nm時為3.5×109 #/cm3，扭力4.0 Nm時之數目濃度為3.2×1010 #/cm3。以95無鉛汽油當燃料，排放微粒數目濃度於惰轉時為2.1×109 #/cm3，高轉速時為2.4×108 #/cm3，扭力2.0 Nm時為4.1×108 #/cm3，扭力4.0 Nm時之數目濃度為9.3×109 #/cm3。以92無鉛汽油當燃料，排放微粒之碳含量佔微粒80%以上之比例，其中有機碳佔60%以上，元素碳佔20%左右，碳及有機碳含量隨轉速增加而減少，元素碳含量則隨轉速增加而增加，扭力增加時，有機碳含量增加、元素碳含量減少、離子含量增加。以95無鉛汽油當燃料，排放微粒之碳含量佔微粒75%以上之比例，其中有機碳佔60%以上，元素碳佔15%左右，碳及有機碳含量隨轉速增加而減少，扭力增加時，有機碳含量增加、元素碳含量減少、離子含量減少。92及95無鉛汽油燃燒後排放粒狀污染物濃度隨著大氣溫度的增加而增加，於惰轉、低轉速及高轉速皆有相同之趨勢，不同大氣溫度情況下以20℃惰轉時粒徑最大(分別為0.48及0.12μm)，隨著大氣溫度的增加燃燒室溫度增加，汽油燃料燃燒較完全，所排放微粒粒徑減小，於35℃時各轉速粒徑最小(約0.135~0.12 μm)。

關鍵字

四行程機車引擎 ； 引擎動力計 ； 微粒

並列摘要

In Taiwan, motor vehicles are a major source of air pollution. There are about twenty-million motor vehicles in Taiwan. Particles emitted from motorcycles and formed by gas reaction or condenation deteriorate ambient air quality. Not many researches had been conducted to study motorcycle emissions. Researches on exhaust gas from motorcycle were most focused on effect of engine speed.
In this thesis, the particle measurement system consistedof a 4-stroke Motorcycle Engine (125 c.c.), Dynamometer, Electrical Low-Pressure Impactor (ELPI)、Micro-Orifice Uniform Deposit Impactor (MOUDI) and Nano Micro-Orifice Uniform Deposit Impactor (Nano-MOUDI). Different fuels, 92 unleaded gasoline and 95 unleaded gasoline, were used to study their effects on the particulate emission. An Ion Chromatography (IC) and an Element Analyzer (EA) were used to analyze characterization of particles.
The results suggested that particle number concentration decreased as engine rotational speeds increased. However, it increased as torque and atmospheric temperature increased. Using 92 unleaded gasoline as the tested fuel, the results suggested that number concentration was 5.6×1010 #/cm3 when rotational speed at idle and number concentration was 1.1×1010 #/cm3 when rotational speed at high speed (5775 rpm). Moreover, number concentration was 3.5×109 #/cm3 when torque was 2.0 Nm (at 3885 rpm), number concentration was 3.2×1010 #/cm3 when torque was 4.0 Nm (at 3885 rpm). Using 95 unleaded gasoline as the tested fuel, the results suggested that number concentration was 2.1×109 #/cm3 when rotational speed at idle and number concentration was 2.4×108 #/cm3 when rotational speed at high speed (5775 rpm). Moreover, number concentration was 4.1×108 #/cm3 when torque was 2.0 Nm (at 3885 rpm), number concentration was 9.3×109 #/cm3 when torque was 4.0 Nm (at 3885 rpm). By using 92 unleaded gasoline and 95 unleaded gasoline as the tesed fuel, carbon content and organic carbon content decreased as rotational speeds increased, while element carbon content increased as rotational speeds increased. Organic carbon content increased as torque increased, while element carbon content decreased as torque increased. Using 92 unleaded gasoline and 95 unleaded gasoline as tested fuels, the particle number concentration increased as atmospheric temperature increased. Particle diameter decreased as atmospheric temperature increased.

並列關鍵字

4-stroke Motorcycle Engine ； Dynamometer ； Particles

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