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Diesel spray simulation with a Lagrangian approach for the dispersed phase and a Eulerian approach for the continuum phase is known to be sensitive to mesh resolution and its structure. Inaddition a dependency to turbulent length scale at nozzle exit has been reported in the computational literature. The aim of this work is to quantify these sensitivities and verify computational results for an extensive series of parameters on the basis of detailed shadowgraphy and PDA experiments in a constant volume bomb. The analysis consists of temporal and spatial resolution studies, initial turbulent length scale variation, investigation of the sensitivity to two different atomization models and the influence of the injection direction to the mesh orientation. This study has been done both for non-evaporating and evaporating diesel sprays. The calculations showed a high mesh sensitivity on spray penetration.

The three components of the velocity were measured by laser Doppler velocimetry at 35 locations in each of the six intake ports of a single-cylinder I.C. engine motored at 600, 900, and 1200 rpm. The intake ports were designed to impart both swirl and roll to the air. Pressure was also measured at the intake and exhaust. The detailed information is valuable mostly for computations of engine flows and for the assessment of multidimensional models. However the following trends were observed. The intake velocity is affected by resonant pressure waves. The flows in the six ports tend to be similar. The three components of the ensemble-averaged velocity generally have uniform profiles across the port area, whereas the fluctuation intensities are higher at the top of the port. All velocities tend to be higher at the beginning and end of intake.