The Simultaneous Reduction of NOx and PM Using Ultra-Cooled EGR and Retarded Injection Timing in a Diesel Engine
The Simultaneous Reduction of NOx and PM Using Ultra-Cooled EGR and Retarded Injection Timing in a Diesel Engine
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DOI：
10.1080/15435075.2013.841164
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发表时间：
2015-04
影响因子：
3.3
通讯作者：
P. Brijesh;A. Chowdhury;S. Sreedhara
中科院分区：
文献类型：
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作者：
P. Brijesh;A. Chowdhury;S. Sreedhara
现在，柴油发动机比汽油发动机更受欢迎，因为它们具有无可争议的燃油经济性和更高的扭矩输出。然而，在不影响燃油经济性的情况下满足严格的排放标准是柴油发动机的主要挑战。本文对可变压缩比（VCR）发动机的喷油参数、压缩比（CR）和过冷废气再循环（EGR）量等参数进行了优化，以实现同时降低NOx和碳烟的低温燃烧模式。田口分析被用来进行最少数量的实验运行，并仍然得到大量的测试用例的本质。这些参数对发动机性能和排放的影响也进行了研究的信噪比（SN）分析的帮助下。SN比分析结果表明，喷油正时、CR和过冷EGR是主要影响因素，而喷油压力在研究范围内对所选响应变量的影响并不显著。对于具有优化的输入参数的运行，已经观察到更平坦和更宽的HRR迹线，因此同时减少NOx和PM排放。NOx和烟尘分别减少了98%和60%，制动热效率（BTE）增加了5%。较高的HC和CO排放量的值被发现与优化的参数运行，但这些可以很容易地通过使用催化转化器，一个简单的设备减少。
Now-a-days, diesel engines are more popular over gasoline engines due to their undisputed benefit of fuel economy and higher torque output. However, meeting the stringent emission norms without affecting fuel economy is a major challenge with diesel engines. In this paper, optimization of various parameters like injection parameters, compression ratio (CR) and amount of ultra-cooled exhaust gas recirculation (EGR) has been done for a variable CR (VCR) engine, to achieve low-temperature combustion (LTC) mode by which simultaneous reduction of NOx and soot may be obtained. Taguchi analysis was employed to carry out minimum number of experimental runs and still get the essence of large number of test cases. Effect of those parameters on engine performance and exhaust emissions has also been studied with the help of signal-to-noise (SN) ratio analysis. Results of SN ratio analysis indicate that injection timing, CR and ultra-cooled EGR are the dominant factors while the effect of injection pressure, in range of study, is not much significant for chosen response variables. Flatter and wider HRR traces, hence simultaneous reduction in NOx and PM emissions has been observed for runs having optimized input parameters. NOx and soot found to be reduced by 98% and 60%, respectively, with an increase in brake thermal efficiency (BTE) by 5%. Higher values of HC and CO emissions were found for runs with optimized parameters, but these can be easily reduced by using a catalytic converter, a simple device.