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A previously developed multi-zone direct-injection (DI) diesel combustion model was implemented into a turbocharged diesel engine full cycle simulation tool DIESEL-RK. 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 modeling process is assumed to have an arbitrary axi-symmetric shape.

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.

A multi-zone, direct-injection (DI) diesel combustion model, the so-called RK-model, has been developed and implemented in a full cycle simulation of a turbocharged engine. The combustion model takes into account: transient evolution of fuel sprays, interaction of sprays with swirl and walls, evolution of near-wall flow formed after spray-wall impingement depending on impingement angle and local swirl velocity, interaction of Near-Wall Flows (NWF) formed by adjacent sprays, influence of temperatures of gas and walls in the zones on evaporation rate. In the model the fuel spray is split into a number of specific zones with different evaporation conditions including zone on the cylinder liner and on the cylinder head. The piston bowl is assumed to be a body of revolution with arbitrary shape. The combustion model supports central and non-central injector as well as the side injection system. NOx formation model uses Detail Kinetic Mechanism (199 reactions with 33 species).

A multi-zone, direct-injection (DI) diesel combustion model, the so-called RK-model, has been developed and implemented in a full cycle simulation of a turbocharged engine. The combustion model takes into account: transient evolution of fuel sprays, interaction of sprays with swirl and walls, evolution of near-wall flow formed after spray-wall impingement depending on impingement angle and swirl, fuel-air mixing, interaction of near-wall flows formed by adjacent sprays, evaporation conditions for different zones. In the model the fuel spray is divided into a number of zones with different evaporation conditions. The piston bowl is assumed to be a body of revolution of otherwise arbitrary shape. Submodels of soot and NOx formation are included. The model has been validated by experimental data obtained from high-speed and medium-speed engines over the whole operating range; a good agreement has been achieved without recalibration for different operating modes.

A multi-zone model of diesel sprays evolution and combustion named as RK-model has been developed. The model with submodels of NO and soot formation has been implemented into ICE thermodynamic analysis software (DIESEL-RK). The RK-model takes into account: the shape of injection profile, including split injection; drop sizes; direction of each spray in the combustion chamber; the swirl intensity; the piston bowl shape. Evolution of wall surface flows generated by each spray depends on the spray and wall impingement angle and the swirl intensity. Interaction between near-wall flows (further named wall surface flows) generated by the adjacent sprays is taken into account. The method considers hitting of fuel on the cylinder head and liner surfaces. The evaporation rate in each zone is determined by Nusselt number for the diffusion process, the pressure and the temperature, including temperatures of different walls where a fuel spray gets.