Effects of High and Low Pressure EGR on Heavy-Duty Diesel Engine Performance

WANG Zuofeng; ZHONG Kun; JIA Shuai; SUN Ting

Vehicle Engine ›› 2021, Vol. 0 ›› Issue (5) : 22-27.

WANG Zuofeng^1,2,ZHONG Kun^1,2,JIA Shuai^1,2,SUN Ting^1,2

Author information +

History +

Abstract

An experimental study was performed on a common-rail heavy-duty diesel engine with two-stage supercharging, which was about the effect mechanism of two-stage supercharging system, intake and exhaust manifold parameters and emission characteristics under different conditions. The results show that only low pressure EGR has little effect on the two-stage supercharging and intake and exhaust manifold parameters, but only high pressure EGR has an apparent effect. The low pressure EGR can improve the Trade-off relationship of NO_x with BSFC and soot respectively in medium and high loads at medium speed and the high pressure EGR can also improve the Trade-off relationship of NO_x with BSFC at high speed, but with the deterioration of soot emission. There is a contradiction at high speed and high load that the fuel consumption drops due to the reduced pump loss and increases due to the deteriorated combustion, which will not occur at high speed and low load. Accordingly, it should be adopted to mainly use low pressure EGR in medium and high loads at medium speed, mainly use high pressure EGR at high speed and low load, and use high pressure EGR assisted with low pressure EGR at high speed and high load, and hence both the low emission and the good fuel economy and soot can be achieved.

Key words

heavy-duty diesel engine / EGR / emission / fuel economy

Cite this article

EndNote

Ris (Procite)

Bibtex

Download Citations

WANG Zuofeng,ZHONG Kun,JIA Shuai,SUN Ting. Effects of High and Low Pressure EGR on Heavy-Duty Diesel Engine Performance[J]. Vehicle Engine. 2021, 0(5): 22-27