Study of Two Phase Flow Breakup Behavior for Application to Solid Rocket Motor Nozzle

This paper presents a method of characterizing liquid breakup phenomena using a probability distribution flow pattern and compares CFD results of a straight channel two-phase flow using k-ε, SST k-ω and Reynolds Stress Model (RSM). Examination of liquid breakup level is essential for solving erosion phenomenon of solid fuel rocket motor (SRM), due to their use aluminum based solid propellants. During the propellant combustion, the aluminum oxidizes into alumina (Al₂O₃), which tends to agglomerate into molten droplets under a certain flow conditions. The molten droplets can then impinge on the combustion chamber walls, and flow along the nozzle wall. Such agglomerated aluminum leads to erosive damages to the geometry of de Laval nozzle and reduces the SRM propulsion performance. The volume fraction (VF) contour of the liquid can be used as the raw data for time average flow VF contour of straight channel. The flow shows the probability distribution of two-phase boundary which is mostly controlled by the features of different turbulence models. Those results will be used for future comparison to two-phase flow experiment as model selection reference of SRM two-phase supersonic flow simulation.