000K utf8 1100 2019$c2019-10-11 1500 eng 2050 urn:nbn:de:hbz:465-20220331-094354-5 2051 10.1177/1468087419881535 3000 Geschwindner, Christopher 3010 Böhm, Benjamin 3010 De la Morena, Joaquin 3010 Kaiser, Sebastian A. 3010 Kranz, Patrick 3010 Schmidt, Marius 3010 Welch, Cooper 4000 Analysis of the interaction of Spray G and in-cylinder flow in two optical engines for late gasoline direct injection [Geschwindner, Christopher] 4209 An investigation of the interaction between the in-cylinder flow and the spray topology in two spray-guided direct injection optical engines is reported. The bulk flow field in the combustion chamber is characterized using particle image velocimetry. Geometrical parameters such as the axial penetration and the spray angle of the liquid spray are measured using Mie scatter imaging and/or diffuse back-illumination. The measured parameters are compared with data from a constant volume chamber available in the literature. For a late injection strategy, the so-called ECN Spray G standard condition, the mean values of the spray penetration do not seem to be significantly perturbed by the in-cylinder flow motion until the plumes approach the piston surface. However, spray probability maps reveal that cycle-to-cycle fluctuations of the spatial distribution of the liquid spray are affected by the magnitude of the in-cylinder flow. Particle image velocimetry during injection shows that the flow field in the vicinity of the spray plumes is heavily influenced by air entrainment, and that an upward flow in-between spray plumes develops. Consistent with previous research that demonstrated the importance of the latter flow structure for the prevention of spray collapse, it is found that increased in-cylinder flow magnitudes due to increased intake valve lifts or engine speeds enhance the spray-shape stability. Compared with cases without injection, the influence of the spray on the in-cylinder flow field is still noticeable approximately 2.5 ms after the start of injection. 4950 https://doi.org/10.1177/1468087419881535$xR$3Volltext$534 4950 https://nbn-resolving.org/urn:nbn:de:hbz:465-20220331-094354-5$xR$3Volltext$534 4961 https://duepublico2.uni-due.de/receive/duepublico_mods_00071827 5051 620 5550 diffuse back-illumination 5550 Engine Combustion Network 5550 Mie scattering 5550 particle image velocimetry 5550 spark-ignition direct injection 5550 spray angle 5550 spray collapse 5550 spray–flow interaction 5550 Spray G 5550 spray penetration