Technical Note: Investigation on emission characteristics of a compression ignition engine with oxygenated fuels and exhaust gas recirculation

Abstract

Investigations of emission characteristics were carried out on a compression ignition, dimethyl ether engine (DME) with exhaust gas recirculation (EGR) and on a diesel engine with a dimethyl carbonate (DMC) additive. The experimental results show that the DME engine with EGR can simultaneously reduce smoke and NO x emissions. The NO x can be reduced by about 20 per cent for every 10 per cent of EGR introduction, while smoke remains at zero. The diesel equivalent brake speci®c fuel consumption (b.s.f.c.) shows a slight decrease when DMC is added, while the eective thermal eciency shows a slight improvement. It is found that the smoke reduction rate and smoke show a linear relationship with DMC percentage or oxygen mass percentage in the diesel fuel. For the speci®c brake mean eective pressure (b.m.e.p.), smoke will be reduced by 20 per cent for every 10 per cent DMC added and by 40 per cent when the oxygen mass percentage in the fuel reaches 10 per cent. The CO decreases when DMC is added, while NO x shows an increase. This dierence is pronounced at a high b.m.e.p. For the speci®c b.m.e.p., CO and NO x show a linear relationship with DMC mass percentage in the fuel; CO will be reduced by 20 per cent while NO x will be increased by 20 per cent for every 10 per cent DMC added.

Dimethyl Carbonate as a Promising Oxygenated Fuel for Combustion: A Review

“…Wang et al [64] investigated the emission characteristics of a diesel engine with oxygenated fuels and exhaust gas recirculation. Fuel consumption increased with the increase of DMC addition percentage in the mixed fuels owing to the low lower-heat value of DMC compared to base fuel.…”

Application of an enhanced Taguchi method for simultaneous reduction of smoke and NOx emissions using oxygenated additives and retarded injection timing in a stationary diesel engine

“…Blend proportions greater than 20 % have been reported to cause engine instability, fluctuations in engine speed and losses in power output [11] [15] [27]. Hence the maximum proportion of oxygenates in the blend is restricted to 20 %.…”

“…It was suggested that adding oxygenates is a promising approach to solve the problem of simultaneously reducing NOx and smoke emissions due to the inherent trade-off relationship between them in a traditional diesel engine [8]. However, many studies have found that increasing the proportion of oxygenates in diesel can either result in increasing the levels of NOx emissions [9][10][11][12][13] or do not affect their levels at all [14][15][16]. Burnt gas temperature and the duration spent by the gas at that temperature inside the combustion chamber are the two factors that affect NOx levels.…”

Investigation of Performance and Emission Characteristics of a Compression Ignition Engine with Oxygenated Fuel

“…Wang et al [2] and Miyamoto et al [3] studied emissions and combustion with different oxygenated compounds and EGR. They realized that significant improvements in smoke, particulate matter, NO x , HC and thermal efficiency with oxygenates.…”