Abstract
This study aims to better understand the aluminum oxide agglomerates break-up mechanism, consequently determining the best solution for the solid rocket motor (SRM) nozzle erosion problem. Two-phase air-water flow experimental investigation was conducted as a substitute for liquid aluminum agglomerates and exhaust combustion gases. The results show that increasing the exhaust air velocity enhances the droplet's break-up tendency in terms of reducing the average diameter and increasing droplets number per the testing channel volume.
Numerical models were constructed and validated using the experimental results. The percentage error in the droplets' average diameter and number is between 6–15% and 8-18%. Furthermore, the effect of reducing the liquid surface tension was studied. The results showed that it facilitates water bodies' separation from the interface surface, as a result of the reduced bounding forces between surface's molecules, which enhances the break-up process (0.5-17% increase in the droplets' average diameter and 4-100% increase in its number) and reduce the droplets impact on the nozzle walls, hence reduce the SRM nozzle erosion problem.
The matching of a “one-dimensional” numerical simulation and experiment results for low viscosity Newtonian and non-Newtonian fluids during fast filament stretching and subsequent break-up