Abstract
Emissions from diesel engines can be limited and potentially decreased by modifying the fuel chemical composition through additive insertion. One class of additives that have shown to be particularly efficient in the reduction of the particulates from the combustion of diesel fuels are oxygenated compounds. In the present study we investigate the effect of tripropylene glycol methyl ether (TPGME) and two polyoxymethylene dimethyl ethers (POMDME or OMEs) on soot formation in a laminar diesel diffusion flame. From the evaluation of soot volume fraction by laser-induced incandescence (LII) measurements we could observe that OME additives have a substantial capability (higher compared to TPGME) to decrease the particle concentration, which drops by up to 36% with respect to the pure diesel fuel. We also note a reduction in particle aggregate size, determined by wide-angle light scattering (WALS) measurements, which is more pronounced in the case of OME–diesel blends. The effects we observe can be correlated to the higher amount of oxygen content in the OME molecules. Moreover, both additives investigated seem to have almost no impact on the local soot temperature which could in turn play a key role in the production of soot particles.
Highlights
Environmental particulate matter (PM) is considered a serious hazard for human health because of its harmful impact on the respiratory system
The effect of tripropylene glycol methyl ether (TPGME), OME2 and OME3–5 on soot properties was investigated in a laminar diesel diffusion flame by two-color pyrometry, laser-induced incandescence and wide-angle light scattering
The additives were mixed with pure diesel in different concentrations, namely 1%, 3%, and 9% vol Eventually, the results were compared with those obtained from the measurements on the baseline diesel
Summary
Environmental particulate matter (PM) is considered a serious hazard for human health because of its harmful impact on the respiratory system. Recent studies performed inside or at the exhaust of diesel engines highlight the tendency of some ether compounds, namely glycol ethers and longchain oxymethylene dimethyl ethers (OMEs), to efficiently act as soot reducers [17,18,19] These species have densities similar to that of diesel and are toxicologically uncritical. In this study we investigate the effect of oxygenated species on the soot volume fraction and soot aggregate size in a laminar diesel diffusion flame. This environment provides simplified conditions, where physical effects typical for an engine are bypassed and the influence of the chemical structure of the blended fuel on particle formation can be isolated. The results can be used as dataset for the validation of diesel soot models, where usually the chemical structure of the fuel is one of the most important input parameters and plays a key role in the model’s outcome
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
