Effect of Oxygenated Fuel on Combustion and Emissions in a Light-Duty Turbo Diesel Engine

Abstract

In previous studies on a single-cylinder IDI diesel engine and a V-8 DI turbo diesel engine, significant reductions in particulate matter emissions were observed with the blends of glycol ethers in diesel fuel. In this study, experiments on the effects of oxygenated fuels on emissions and combustion were performed in a 4-cylinder TDI diesel engine. A blend of 20 wt % monoglyme and 80 wt % diglyme, referred to as CETANER, has been examined as a diesel reformulating agent. Blend ratios were considered to provide approximately 2, 4, and 6 wt % oxygen to lowsulfur diesel fuel. Gaseous and particulate emission measurements, as well as heat release rate analysis, have been used to address how emissions and combustion scale with increasing weight percent oxygen in the fuel. The results demonstrate that the oxygenated fuel provides significant reduction in particulate matter with a small penalty on NO x emission, especially at high load. This oxygenated fuel effect may result from an enhanced concentration of oxygen atoms in the over-rich mixture thereby contributing to soot suppression and thermal NO x formation through a shift to a leaner mixture. Low load results imply that the combined effect of relatively high exhaust gas recirculation (EGR) ratio and oxygen addition contributes to both NO x and soot reduction through a combination of flame temperature decrease and suppression of soot precursors. The combined effects on thermal NO x reduction at low load appear to be confirmed by heat release analysis, which indicates a small reduction in premixed burn peak and in-cylinder pressure. The slight reduction in HC and CO emissions under most conditions indicates an improvement of combustion efficiency with the use of oxygen addition. This result also represents the potential of diesel reformulation coupled with high EGR ratio for a better particulate/NO x tradeoff. Particulate morphology, as seen in transmission electron microscopy (TEM) micrographs, shows that enhanced oxidation of unburned hydrocarbon due to oxygen addition leaves a less agglomerated particulate structure especially at low mode, leading to a higher number density of smaller particles and a lower particulate mass.

Eksplorasi Minyak Atsiri Sebagai Bioaditif Bahan Bakar Solar

“…Selain itu, dua atom oksigen pada eugenol (Kadarohman, 2003), yaitu komponen utama minyak cengkeh, dapat berperan sebagai "penyedia oksigen" secara internal. Hal ini sesuai dengan Song (2001) yang mengemukakan bahwa penambahan zat aditif 'penyedia oksigen' pada bahan bakar solar berperan untuk meningkatkan bilangan setana (cetane number), serta temuan Choi (1999) yang mengemukakan bahwa atom oksigen di dalam bahan bakar akan berperan untuk mengoksidasi jelaga dan gas karbon monoksida (CO), sehingga pembakaran menjadi lebih sempurna.…”

“…Song (2001) dan Choi (1999) mengemukakan zat aditif 'penyedia oksigen' pada bahan bakar solar berperan untuk meningkatkan bilangan setana (cetane number), sehingga pembakaran menjadi lebih sempurna.…”

Características da combustão de um motor diesel com injeção direta de misturas de óleo diesel e etanol e injeção indireta de etanol

“…Pesquisas para aumentar a eficiência de conversão do combustível e reduzir os níveis de emissões são realizadas por modificações construtivas, controle da formação da mistura ou modificação dos combustíveis [3]. A emissão de NOX e MP é um dos maiores problemas de poluição das grandes cidades, tornando a busca por combustíveis menos poluentes cada vez mais intensa [4][5][6][7].…”

Impact of Dme-Diesel Fuel Blend Properties on Diesel Fuel Injection Systems

“…To that end, the viscosity measurements of DME blended with various fuels and with various lubricity enhancing additives is intended to assess whether the viscosity of DME can be increased with only modest treat rates of other substances. The work presented here is the product of a joint effort by the Penn State Energy Institute and Multi-discipline Tribology Group, which have collaborated on studies of several alternative fuels including biodiesel fuels [27] and oxygenated fuels [28]. Significant improvements in friction and wear were demonstrated by vapor-phase oxidation of biodiesel fuels [29].…”