A 1-D Numerical Analysis on the Control of HCCI Combustion in a CI Engine Through Exhaust Gas Recirculation

以廢氣迴流控制壓燃引擎HCCI操作之一維數值分析

阮德慶(Duc-Khanh Nguyen) ； 黎英俊(Anh-Tuan Le) ； 陳氏秋香(Thu-Huong Tran Thi) ； 吳明勳(Ming-Hsun Wu)

《中國機械工程學刊》 39卷2期 (2018/04) Pp. 179-186

摘要

In this study, we investigated the potential of combustion control of a diesel engine operating in homogeneous charge compression ignition (HCCI) mode through 1-D engine gas dynamic simulation (AVL BOOST). Effects of parameters including the content of residual gas, the ratio of external EGR, and its temperature on engine thermal efficiency were studied. The results showed that the engine efficiency increased with more residual gas at lean conditions. The temperature of recirculated exhaust gas is an important parameter for auto-ignition timing control. As the exhaust gas temperature becomes higher, combustion initiation occurs earlier, further results in the reduction of engine efficiency. The indicated efficiency of the engine operating in HCCI mode peaks at 43.19% with lambda of 3.53 without EGR. The simulation predicts that the efficiency can be improved to 44.07% by using leaner mixture and EGR.

關鍵字

HCCI ； exhaust gas recirculation ； combustion control ； engine 1-D ； simulation

並列摘要

本研究之目的在於透過一維引擎氣動力模擬，探討不同比例的引擎廢氣迴流對於一HCCI 引擎性能之影響。研究中探討了包括廢氣組成、迴流比例、殘餘氣體溫度等廢棄迴流參數對於燃燒起始時點與效率的影響。分析結果顯示引擎效率在貧油條件下會隨缸內已燃氣增加而提高。迴流廢氣之溫度為控制自點火時點之關鍵參數。較高溫度會使燃燒開始提前，造成效率降低。於為3.53 時，模擬所得最高效率為43.19%，而當為3.76 時，迴流比為36%及迴流氣溫度為353 K 時，效率則提升至44.07 %。