A detailed chemistry-based CFD model was developed to simulate the diesel spray combustion and emission process. A reaction mechanism of n-heptane is coupled with a reduced NOx mechanism to simulate diesel fuel oxidation and NOx formation. The soot emission process is simulated by a phenomenological soot model that uses a competing formation and oxidation rate formulation. The model is applied ...

In this computational research, the separate and simultaneous impacts of diesel direct injection timing, fuel spraying cone angle, and hydrogen gas addition on combustion characteristics, output emissions, and performance in a single-cylinder direct injection diesel engine was studied. In order to conduct the simulations, valid and reliable models for combustion, break-up, and for turbulence wa...

............................................................................................................. I ACKNOWLEDGEMENTS .................................................................................... II LIST OF PAPERS................................................................................................. III BACKGROUND.........................................................

this paper is the representation of the computational and experimental methods of a new injector nozzle for a sequential port injection cng engine. the objective of this study was to review the previous research in the development of gaseous fuel injector for port injection cng engine converted from diesel engine. next, a simulation of the fuel flow of the new injector nozzle was made using flu...

A new combustion model is developed and applied to simulate combustion in dual-fuel engines in which the premixed natural gas is ignited by the combustion flame initiated by a diesel spray. The model consists of a diesel auto-ignition model and a flame propagation model. A G-equation model previously developed to simulate SI engine combustion was incorporated with an auto-ignition model to simu...

Submodels are developed for injection, evaporation and wall impingement of a liquid LPG spray. The injection model determines the quality of fuel as two-phase choke flow at the nozzle exit. Wind tunnel experiments show the spray penetration more sensitive to ambient flow velocity than to injection pressure. Most evaporation occurs during choking, while heat transfer from surrounding air has a n...

The efficiency and emissions of internal combustion (IC) engines are closely tied to the formation of the combustible air-fuel mixture. Direct-injection engines have become more common due to their increased practical flexibility and efficiency, and sprays dominate mixture formation in these engines. Spray formation, or rather the transition from a cylindrical liquid jet to a field of isolated ...

I h e interaction of a dense spray diffusion flame with a non-decaying potential vortex has been investigated theoretically. A similwity solution for the local ~tmctiire of the diffusion flamelet in the vortex field has been determined. The global diffusion flame contour generated by the vortcx has been determined by patching the flamelet solutions at different distances from the vortex center ...