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The purpose of this study is to simulate combustion, soot and NOx-emissions in the world's largest medium speed diesel V-engine, the W64V, based on simulation results of in line-engine W64L. The simulation tool was the modified KIVA2-CFD code to which the following submodels were added: The Magnussen EDC ( Eddy Dissipation Concept ) turbulent mixing combustion model, the extended Zeldovich NO model and a simple rebounding model for the droplet wall impingement. Further the Tesner&Magnussen soot formation and combustion model was implemented in the code and the modified TAB model was used for the spray. The simulation results, such as the cylinder pressure, the heat release rate and the cumulative heat release were compared with the results of a thermodynamic two zone model because the V-engine is under design and therefore measured quantities are not available.

The combustion process and NOx emission of the world's largest medium speed diesel engine, the Wärtsilä W64L (W64L), were simulated with the modified Kiva2-CFD code. The following submodels were added to the standard Kiva2 code: The Magnussen EDC (Eddy Dissipation Concept) turbulent mixing combustion model, the extended Zeldovich NO model and a simple rebounding model for the droplet wall impingement. The Tesner&Magnussen soot formation and combustion model was implemented in the code, but it has not yet been used in this stage. The modified TAB model was used for the spray. The simulation results, such as the cylinder pressure, the heat release rate and the cumulative heat release were compared to the measured values of the W64L engine. The spray model correctness was tested by comparing the predicted spray tip penetration with Hiroyasu's correlation at room temperature conditions.

The purpose of the paper is to present injection results of heavy fuel spray at room temperature conditions and combustion predictions in a medium speed diesel engine using the k-ε turbulence model in KIVA2. The work consists of two main parts. In the first, the heavy fuel spray is simulated at cold test chamber conditions in which the density of gas is of the same order of magnitude as in the engine at the end of compression. The predicted spray tip penetration and droplet sizes are compared to the measured values. The second part deals with the combustion simulation using the Magnussen and Hjertager ( M&H ) or Magnussen Eddy Dissipation Concept ( EDC ) turbulent diffusion combustion model. The cylinder pressures and heat release in the simulation are compared to the measured values.