密閉式循環柴油引擎，於進氣處添加異丙醇之性能及排氣汙染之研究

Study of Performance and Exhaust Emissions for Closed Cycle Diesel Engines Adding Isopropanol at The Inlet Port

本研究係將電子控制噴射異丙醇、EGR系統與進氣加熱裝置安裝在密閉式循環柴油引擎CCDE(Closed Cycle Diesel Engine)上，改變引擎轉速、負荷、異丙醇質量分率、進氣溫度及氫氧化鉀濃度進行量測。並使用溫度及酸鹼度圖控顯示，可監控CCDE的即時運轉狀態。結果顯示於進氣處噴入異丙醇，可減少密閉式循環引擎的NOX、Smoke與PM2.5的污染物，最大下降率分別為27.15%、19.61%及30.45%。增加氫氧化鉀(KOH)比例可吸收密閉式循環引擎排放廢氣中的污染物，且能有效改善密閉式循環引擎的排放污染，而CO2、CO、NOX、HC、Smoke及PM2.5最大下降率分別為6.94%、18.61%、12.13%、10.68%、14.92%及17.78%。同時以KIVA-3V程式碼進行暫態噴霧燃燒與紊流數值模擬分析，並且修改部份副程式，加入詳細化學動力，以配合進氣處噴入異丙醇、進氣溫度與EGR(Exhaust Gas Recirculation)比率，將計算值與實驗數據相互印證，得到計算值與實驗數據趨勢一致。

"This study is to install the electronic control injection isopropanol, EGR system and intake heating device in the closed cycle diesel engine (CCDE) with changing engine speed, load, isopropanol mass fraction, intake temperature and KOH concentration for measurement. The real-time operation status of CCDE can be monitored by using temper-ature and acidity graph display. The results show that the injection of isopropanol at intake port can reduce the emission pollution of NOX up to 27.15%、Smoke up to19.61% and PM2.5 up to 30.45% from the closed cycle engine. Increasing the KOH ratio absorbs exhaust gases from closed cycle engines can decrease CO2 up to 6.94%, CO up to18.61%, NOX up to12.13%, HC up to10.68%, Smoke up to 14.92%, and PM2.5 up to17.78%. At the same time, the KIVA-3V code was employed for transient spray combustion and turbulence numerical simulation analysis, and parts of the program was modified by adding detailed chemical reactions, to match addition of isopropanol at intake port, charge tempera-ture and EGR ratio. The calculation results and experimental data mutually confirmed, and the trends between calcu-lation results and experimental data are found consistent."