Effects of piston shapes and swirl ratios on combustion and emissions of a micro diesel pilot-ignition natural gas engine

Abstract

A reduced chemical kinetic mechanism was coupled with computational fluid dynamics (CFD) model to explore the detailed influencing mechanism of swirl ratios and piston shapes on a micro diesel pilot...

Experimental and computational study on the effects of exhaust gas recirculation on thermodynamics, combustion and emission characteristics of a diesel pilot ignition natural gas engine

“…The results indicate a critical pilot energy proportion affecting stability, with early ignition diesel injection improving thermal efficiency and reducing UHC and CO emissions, though occasionally worsening NOx emissions, while improving pilot quality can expedite combustion and improve thermal efficiency by as much as 47.7%. Fu et al 14 investigated the effects of swirl ratios and piston shapes in a DPI NG engine. The simulations reveal that Pmax and maximum HRR exhibit an initial rise followed by a decline with the swirl ratio, while ignition delay shortens significantly with higher swirl ratios but lengthens with larger opening sizes and shallower groove depths.…”