Abstract
In order to gain better control over the combustion process, a new type of injection concept was introduced in a previous paper by the authors [1]. Rotating the injector in a DI Diesel engine is a powerful way for the engine developer to influence the fuel-distribution within the combustion chamber.
The rotating injector has in this work been implemented onto a modern 4-valve engine. The injector has speed capability up to 10 000 rpm in both directions by the use of an electric motor drive. The power requirement is modest.
The tests reveal that the rotating injector strongly affects the combustion and formation of emissions. The greatest impact was found for soot, which at 1000 rpm and an indicated pressure of 6 bar could be reduced by 74 % by rotating the injector counter-swirl at 3350 rpm. This was attributed to more efficient air-fuel mixing which also reduced the ignition delay and made the mixing-controlled burn more intense. The impact on NO was smaller and showed an opposite behavior to soot. Generally, the sensitivity to changes in injector speed was highest at low injector speeds. A relationship with swirl is found for co-swirl rotation.