|
|
Effects of EGR ratios on combustion process and emission with nbutanol/diesel blend |
School of Automotive and Traffic Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China) |
|
|
Abstract For different EGR rates, the bench tests of diesel engine were conducted with 10%nbutanol mass fraction in diesel (N10) as fuel under different working conditions.The influences of EGR rates on combustion, emission and economy characteristics were investigated with nbutanol/diesel blend.The results show that under the same working conditions, with the increasing of EGR rate, the maximum cylinder pressure is decreased, and the crank angle for steep pressure increasing shows backward shift. The main combustion starting moment and the instantaneous heat release peak also show obvious backward shift, and the ignition delay is prolonged with gradually decreased exothermic peak. With the increasing of EGR rate, the HC, CO and Soot emissions of diesel engine are increased, while the emission of Soot is still lower than that with diesel.The NOx emission is decreased gradually, and at high load, the reducing tendency is obvious.At the load of 75%, compared with no EGR, the NOx emission is reduced by 47.2%for EGR rate of 10%, while that is reduced by 86.3% for EGR rate of 20%.
|
Received: 16 July 2015
|
|
|
|
|
|
|