Breakup and atomization of a kerosene jet in crossflow at elevated pressure

Kurzfassung

The breakup, penetration, and atomization of a plain jet of kerosene Jet A-1 fuel in a non-swirling crossflow of air were investigated experimentally at test conditions relevant to LPP (Lean Premixed Prevaporized) combustion for gas turbines. Measurement techniques employed include time-resolved shadowgraphs, Mie-scattering laser light sheets, and Phase-Doppler-Anemometry (PDA). The nozzle diameter was 0.45 mm and its L/D ratio was 1.56. Air velocities lay between 50 m/s and 100 m/s, the air pressure range extended from 1.5 bar to 15 bar and the air temperature was around 290 K. Fuel flowrates were chosen so that the fuel-to-air momentum flux ratio q assumed mainly values between 2 and 18. Two different mechanisms of jet breakup could be discerned and correlations for the jet penetration and lateral dispersion close to the nozzle were derived. Furthermore, the penetration of the spray plume and its representative droplet diameters were determined. Finally, a simple, approximate model to predict liquid fuel penetration is presented.