Numerical Simulation of Spray Process of Fuel Nozzle

Control of exhaust emission and combustion efficiency depend directly on the atomization of the liquid. The research on the atomizing performance of fuel nozzle is certainly important. A model using VOF-LES method has been built to investigate sheet breakup behavior of the main circuit of a pressure swirl atomizer. LES which takes into account of turbulence of fuel and air, has been used to simulate the phenomenon of sheet breakup. Vivid gas-liquid interface, instability wave and primary breakup phenomenon have been captured. The patterns of the sheet breaking-up change with different fuel flux. The mechanism of sheet breakup has been analyzed by combining variations of velocity and turbulent kinetic energy with Kelvin-Helmholtz instability theory and turbulence on circumference. The breakup length captured by simulation agrees well with the results of the semi-empirical formulas.