In this work investigations of the flow-field inside and around a heated, vaporizing diesel-fuel-jet are presented. The experiments are carried out in a high-pressure-chamber at elevated temperatures using a commercial Bosch-Common-Rail Diesel-injection system. The pressure and temperature inside the chamber are chosen according to the conditions in a real engine cylinder after compression. Droplet diameters and velocities inside the fuel jet are measured by means of Phase-Doppler-Anemometry (PDA). In order to obtain the velocities of the gas phase very close to the free penetrating fuel jet by Laser-Doppler-Anemometry (LDA), the air inside the chamber is seeded with Titan-Dioxide (TiO2)-particles. Turbulence values like RMS and length scales are derived from these measurements. In addition to these spatially limited measurements the global flow-field around the penetrating fuel-jet is observed by two-dimensional measurements with Particle-Image-Velocimetry (PIV). From the nozzle exit up to 2/3 of the whole penetration length an air flow perpendicular to the spray axis can be detected. This air-flow into the spray provides the heat transfer and vaporization of the fuel-droplets. The fuel jet contains a high droplet concentration which leads to high intensities in the resulting PIV-images from which discrete spray contours can be calculated. By means of the gas-flow velocity components at this contour the total mass of the absorbed air is calculated. This mass is compared at three injection pressures: 80, 100 and 135 MPa. Further experiments concentrate on a spray impinging straight onto a flat wall. The wall jet leads to additional contributions of air absorption into regions with high droplet concentrations.

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