Performance enhancement of a diesel engine with rotating injector – a numerical study
Improving engine performance is a constant challenge and various methodologies have been adopted by researcher’s world over. In this work, the dispersion characteristics of a rotating injector is studied by varying the umbrella angle (UA) followed by its combustion characteristics and comparing it to a static 3 – hole injector. The present numerical study is bench marked with the experimental data obtained from open literature for a 2 – hole injector with various UA angles. The volume fraction of the dispersed fuel along with its spray structure in relation to spray width is compared. This is done by processing the numerical contour plot using LabView image processing utility with appropriate calibration. From the above study the 130 degree UA injector configuration was found to be effective. The combustion characteristics is now studied for this injector. It is found that the rotating injector has better dispersion and lowers NOx by 14 % when compared to a static injector with a very marginal loss in thermal efficiency. The rotary system has a lower heat release but a wider spread in comparison to a static case. This helps in marginally reducing the in-cylinder temperature and pressure lower NOx.