Evaluation of combustion behavior and pollutants emission of advanced fuel formulations by single cylinder engine experiments

According to the results of several studies concerning the influence of fuel formation on exhaust emissions from diesel engines, a new matrix of twelve fuels was tested in a single cylinder DI diesel engine of conventional technology. The matrix was designed by the partners of the FLOLEV research project, partly founded by the E.U., in the framework JOULE III program. The aim of the project is to study the influence on pollutants emission reduction of modern refining process and fuel additvation wit some alternative fuels and cetane improvers. The fuel matrix is structured into three submatrices. The first sub-matrix is constituted by six fuels which represent different products obtainable with the modern refinery technology. The second and third submatrices were designed to test the influence of cetane improver additives and high- oxygenated fuels respectively. The single-cylinder engine of 0.75 liter of displacement, equipped with a cooled E.G.R. laboratory system, was selected because of its high "sensitivity" to the fuel quality changes. The in-cylinder combustion behavior of twelve fuels was followed with the two-color pyrometry technique and the fast sampling valve technique. The exhaust gaseous emission, as well as particulate and aldehydes emission, were measured. Taking into account the influence of different fuel parameters (cetane number, aromatics, sulfur etc.) on pollutants emissions, the behavior of the six base fuels, and then the potentiality of the relative refining process, can be explained.