Spray Distribution of Plain Orifice Atomizer in Preheated Air Flow

Abstract

An experiment by taking photos of the spray field behind plain orifice atomizer was conducted to study its atomization in preheated air flow. The air flow condition was 0.14~0.2 Mach number and 300~400°C. Fuel-to-air momentum flux ratioQvaried from 0.4 to 9, and Weber numberWecovered the range of 60~140. Photos were analyzed by Matlab image processing toolbox. The results indicate that under the experiment conditions: (1) Under the same temperature, jet breakup length increases withQincreasing, and decreases with the increase ofWe. (2) As the air flow temperature increases from 300°C to 400°C, jet and air flow interaction affect the liquid column breakup more greatly than surface tension. (3) Under the same temperature, spray angle increases with the increase ofQ. (4) As the air flow temperature increases from 300°C to 400°C, evaporation affects the atomization more greatly than pneumatic nebulization.