The interaction of spinning liquid film with swirling gas in cylindrical vessel - Experiments and numerical simulations

Experimental flow visualizations and numerical simulations of the interacti on of a spinning liquid film with a swirling gas in a cylindrical vessel ar e reported A gas/liquid flow that simulates the high-pressure conditions of combustion was successfully visualized in a transparent test chamber. The test chamber was a mockup of a liquid propellant gun ignition system compon ent called the hydrodynamically-stabilized combustor. Water-glycerol mixtur es were used for the liquid, and ballistically compressed helium-nitrogen w as used for the gas. The liquid is injected tangentially along the cylindri cal test chamber wall where it spreads as a spinning film. The gas is then injected tangentially and interacts with the liquid. The flows were insensi tive to the tilt angle of the test chamber and only mildly sensitive to the liquid viscosity. Liquid entrainment by the gas and subsequent atomization occurs promptly (within 2 ms) after the onset of gas injection, and the fl ow in the lest chamber vent passage is a swirling, transonic, two-phase fla w. Two types of three-dimensional simulations of the liquid and gas injecti on into the test chamber were performed using the CRAFT Navier-Stokes code. The first type was of the initial liquid flow only. The second type was of the high-pressure gas injection into the chamber, with the liquid initiali zed in an annulus around the chamber surface with a swirl velocity. The num erical simulations were successful in capturing the primary characteristics of the flow phenomena observed in the experimental flow visualizations. Th is included yielding the observed liquid flow patterns before gas injection and capturing the cellular structure observed after gas injection.