Évaluation expérimentale de la combinaison injection multiple et biodiesel sur les performances et les émissions polluantes d'un moteur diesel

Abstract

Air pollution and oil supply have become major issues lately. Oil dependence and greenhouse gases have to be reduced and the use of alternative fuels such as biodiesel may be a good start. Moreover, biodiesel have been proved to reduce particulates, CO and HC emissions when used in diesel engines. Nevertheless, a 10% increase in NOx emissions is generally found. The use of multiple injection with conventional diesel has shown to simultaneously reduce particulates and NOx emissions even if their formation mechanisms are antagonist. The aim of this study is to evaluate the impact of combining multiple injection strategies and biodiesel on pollutant and particle emissions in a light-duty diesel engine at low load in order to see if NOx emissions can be lowered by such a strategy or not. The experimental study was conducted using a fully instrumented 4 cylinder light duty Renault diesel engine. Fuels were, at first characterized using simple injection. Then, the influence of double injection parameters was evaluated to find an optimized strategy at this operating point. At last, the optimized strategy was compared to simple injection and double injection with pure diesel. The use of an optimized double injection strategy led to the reduction of all pollutant emissions except HC, for all blends, when compared to single injection. But NOx emissions for pure biodiesel were increased. Moreover, a reduction of CO, HC and HCHO was achieved for all blends and pure biodiesel when compared to double injection with pure diesel. However NOx and particulate emissions were found to increase. A new fuel made from biomass but composed of alcanes was tested with a single injection strategy. Every measured pollutant emissions were reduced as well as particulate emissions. Moreover, the degradation of combustion, that usually occurs for late injections, was not as important as with diesel or biodiesel. This could be an interesting avenue to pursue investigation that will lead to the liquid fuel of the future.

Date	28 Aug 2014
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Patrice Seers (Supervisor) & Daniel Rousse (Co-supervisor)