High-pressure internal combustion engines promise high efficiency, but a proper injection strategy to minimize heat losses and pollutant emissions remain a challenge. Previous studies have concluded that two injectors, placed at the piston bowl's rim, simultaneously improve the mixing and reduce the heat losses. The two-injector configuration further improves air utilization while keeping hot zones away from the cylinder walls. This study investigates how the two-injector concept delivers even higher efficiency by providing additional control of spray -and injection angles. Three-dimensional Reynolds-averaged Navier-Stokes simulations examined several umbrella angles, spray-to-spray angles, and injection orientations by comparing the two-injector cases with a reference one-injector case. The study focused on heat transfer reduction, where the two-injector approach reduces the heat transfer losses by up to 14.3 % compared to the reference case. Finally, this study connected the two-injector approach to a waste-heat recovery system through GT-Power 1-D simulations, increasing the importance of heat transfer reduction. The final two-injector system then delivered a 54.4% brake thermal efficiency compared to 53% of the one-injector reference case.
|Original language||English (US)|
|Title of host publication||SAE Technical Paper Series|
|State||Published - Apr 6 2021|
Bibliographical noteKAUST Repository Item: Exported on 2021-05-06
Acknowledgements: This work was sponsored by King Abdullah University of Science and Technology (KAUST) and supported by the KAUST Supercomputing Laboratory (KSL). All simulations were performed on KSL's Shaheen-II supercomputer using CONVERGE CFD software. Convergent Science provided CONVERGE licenses and technical support for this work.
ASJC Scopus subject areas
- Safety, Risk, Reliability and Quality
- Automotive Engineering
- Industrial and Manufacturing Engineering