RT Journal Article ID 4c6e98a429ba8e6b A1 Kirsch, Valeri A1 Reddemann, Manuel Armin A1 Palmer, Johannes A1 Kneer, Reinhold T1 MICROSCOPIC ANALYSIS OF TRANSVERSAL AND AZIMUTHAL SURFACE DISTURBANCES OF HIGH-PRESSURE SPRAYS JF Atomization and Sprays JO AAS YR 2017 FD 2017-10-06 VO 27 IS 9 SP 791 OP 805 K1 spray K1 atomization K1 primary breakup K1 azimuthal disturbances K1 microscopy K1 diesel K1 boundary layer instability AB A microscopic system, consisting of a transmitted light microscope and constant-pressure flow vessel, is specifically designed to enable highly resolved high-pressure primary breakup investigations at engine-like densities. At first measurements diesel and two alternative fuels are injected with a standard diesel injector at different ambient pressures. Reynolds and Ohnesorge number are varied over a wide range and several individual mechanisms are identified: an asymmetric outlet flow, the formation of sheets, ligaments, and droplets, and finally the growth of azimuthal and transversal surface disturbances. Wavelength magnitudes of transversal disturbances are in good agreement with existing analytical theories of boundary layer instabilities. Azimuthal disturbances are associated with nozzle internal cavitation. For the given high Weber number azimuthal disturbances are mainly responsible for the overall shape and subsequent breakup of the jet core. PB Begell House LK https://www.dl.begellhouse.com/journals/6a7c7e10642258cc,3d4684f46a8a5e93,4c6e98a429ba8e6b.html