Atomization regime

The crucial limits for the oil-fired and dual-fuel burners are similar to ones for the gas-fired burners (flashback and blow-off) with an additional regime for fhe soot formation that exceeded the limits established by the environmental regulations as well as a reduced atomization regime that is characterized by the occurring liquid droplets at the burner exit. 

Fig. 9.2 Map of secondary atomization regimes as functions of Ohnesorge and Weber numbers, in which the areas representative of automotive gasoline and diesel sprays are identified...

Another BEM modeling of a jet in the atomization regime was done by Park and Heister [24]. They simulated a swirling jet by using the superposition theory, which implements a complex potential containing a vortex. This potential vortex provides a vortical flow that acts as the circumferential pressure caused by the swirling. Annular ligaments pinched from the parent surface are presumed to break into the... 

Fig. 27.2 Jet stability curve dripping flow (A-B-C), Rayleigh breakup (C-D), wind-induced regime (D-F), atomization regime (F-G oiH)...

Rayleigh breakup regime Drop-on-demand regime Atomization regime... 

Jets of 100 mm diameter may penetrate the water layer and reach the bottom. The penetration length increases with the decrease of the jet diameter below a certain diameter, however, the atomization regime is entered with a decrease in the penetration distance but with a higher explosion potential. 

At the lowest ALR, where slug flow is present in the mixing chamber, the oil drop sizes reached about 16-20 % of the initial oil drop size. It may be assumed that the oil drop breakup is inhibited by the incomplete spray drop breakup at this atomization regime. 

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