Experimental investigation of size of fuel droplets formed by steam jet impact

The process of liquid hydrocarbon fuel disintegration into droplets under the action of a supersonic jet of superheated steam was studied by shadow photography and high-speed visualization. During the measurements operating parameters for the conditions of fuel spraying in a real burner were varied for three types of fuel: diesel, oil, and kerosene. For the first time, the photographs of the process of disintegration of various types of liquid hydrocarbon fuel during interaction with a supersonic gas jet were obtained. When oil flows onto the steam jet, thin threads and films of liquid with a chaotic structure are formed. The regime of droplet disintegration corresponds to the catastrophic one. It is shown that the proposed method of fuel spraying provides effective dispersion for high-quality combustion and it can be used in liquid fuel burners, even when burning liquid combustible waste, as well as in low-emission gas turbine engines. Size distributions of fuel droplets in the region of fuel ignition were obtained for different fuel and steam flow rates. The use of a long-focus lens allowed optical magnification of 7:1 and identification of droplets as small as 1 mu m. For diesel and oil, the characteristic droplet size is 2 mu m, and for kerosene, it is 1 mu m.

Automated summary

The study examined the disintegration process of liquid hydrocarbon fuel into droplets under the impact of a superheated steam jet through shadow photography and high-speed visualization. Different types of fuels, including diesel, oil, and kerosene, were tested to determine their spraying conditions in a real burner. The proposed method of fuel spraying was found to provide effective dispersion for high-quality combustion, applicable to liquid fuel burners and low-emission gas turbine engines, even when burning liquid combustible waste.