Technical Paper
Self-Ignition Delay Prediction in PCCI Direct Injection Diesel Engines Using Multi-Zone Spray Combustion Model and Detailed Chemistry
2010-10-05
2010-01-1960
A previously developed multi-zone direct-injection (DI) diesel combustion model has been refined for more accurate simulation of a full cycle of a turbocharged diesel engine. The combustion model takes into account the following features of the spray dynamics: Detailed evolution process of fuel sprays; Interaction of sprays with the in-cylinder swirl and the walls of the combustion chamber; Evolution of a Near-Wall Flow (NWF) formed as a result of a spray-wall impingement as a function of the impingement angle and the local swirl velocity; Interaction of Near-Wall Flows formed by adjacent sprays; Effect of gas and wall temperatures on the evaporation rate in the spray and NWF zones. In the model each fuel spray is split into a number of specific zones with different evaporation conditions. Zones, formed on the cylinder liner surface and on the cylinder head, are also taken into account. The piston bowl in the modelling process is assumed to have an arbitrary axi-symmetric shape.
