Effect of PODE on Emission Characteristics of a China VI Heavy-Duty Diesel Engine

Yanju Wei,Xiaodong Zhu,Zengqiang Zhu,Shenghua Liu,Haoming Gu,Yajie Zhang

doi:10.3390/app12031108

Abstract

With its high cetane number and oxygen content, polyoxymethylene dimethyl ether (PODE) can promote engine combustion and reduce particulate emissions, which has become a key research object of diesel surrogate fuel. This study further explores the effects of blending PODE on emission characteristics of a China VI diesel engine. Diesel/PODE blends with the PODE volume blending ratios of 10%, 20% and 30% have been experimentally investigated in a China VI heavy-duty diesel engine at 1900 rpm and four different loads. Furthermore, the effects of EGR rates (Exhaust Gas Recirculation) rates (0–20%) on combustion and emission characteristics have been also discussed at 1700 r/min engine speed and 50% engine load condition. An exhaust gas analyzer and a particle counter were used to collect NOx, CO and THC emissions and particulate number (PN) emissions. The results show that the CO and THC emissions can be significantly reduced with the increase in the mixing ratio of PODE. Additionally, the particle number concentration can be also reduced, especially at low and high loads. The NOx emissions can be improved by increasing EGR rates. Interestingly, there is a trade-off relationship between PN and NOx emissions. In general, blending PODE can effectively reduce NOx and PN emissions simultaneously.

Highlights

As is well known, diesel engines have been applied widely due to their high thermal efficiency and power performance
Liu et al [8] carried out experiments with a small proportion blending diesel with polyoxydimethyl ether (PODE) on a light-duty diesel engine, which indicated that soot emissions decreased by 90% under high load conditions, and the indicated thermal efficiency could be increased by 2%
The results showed that diesel/PODE (D80P20) and gasoline/PODE (D80G20) could increase the NOx emissions and decrease the soot emissions in most cases compared to diesel

Summary

Introduction

Diesel engines have been applied widely due to their high thermal efficiency and power performance. Liu et al [8] carried out experiments with a small proportion blending diesel with PODE on a light-duty diesel engine, which indicated that soot emissions decreased by 90% under high load conditions, and the indicated thermal efficiency could be increased by 2%. Pellegrini et al [11] measured and evaluated the emission performance of neat PODE and a blend of 10% PODE and 90% commercial diesel fuel in an old Euro-2 diesel car over the NEDC driving cycle Their results showed that PM emissions of neat PODE could be reduced by 77%, which is under the value of Euro 4, but NOx and CO emissions increase, compared to diesel. Some researchers have found positive conclusions about NOx emissions [5,14,15]

Methods

Results

Conclusion