Optimization of Disc Baffle Perforation in Sloshing Nitrous Oxide Tanks

Liquid fuel sloshing during flight introduces destabilizing forces that can compromise a rocket's stability. To mitigate these effects, baffles are employed within fuel tanks to dampen unwanted motion. This study aims to determine the impact of perforation count in disc baffle designs on sloshing behavior of hybrid nitrous oxide fuel, a relatively unexplored variable in multiphase sloshing. The total perforated area in each baffle design is held constant at 18.85 m² to isolate the effects of perforation count. The tank geometry features a height of 1.3716 meters and a diameter of 0.2032 meters, with three baffles spaced evenly at 0.3429-meter intervals. The fuel composition consists of liquid and gaseous nitrous oxide in a 3:1 volume ratio. Sloshing is induced by applying an initial excitation velocity, and metrics such as directional forces, and the damping factor are analyzed. Given these conditions, an optimal perforation count that maximizes the damping factor is calculated, demonstrating peak performance at an intermediate level of baffle perforation, with diminishing returns observed at both higher and lower perforation counts. The approach used here can serve as a starting point to gain a better understanding of the hydrodynamic sloshing behavior of multiphase fluid with respect to the perforation count in disc baffles.