Numerical Simulations of the Sloshing Behavior in Aircraft Hydrogen Tanks for different Flight Maneuvers

Abstract

Sloshing is the dynamic oscillation of liquid within a tank caused by external accelerations. This study quantifies loads in the form of forces exerted by the liquid on the inside of the tank. It focuses on a geometry that represents a realistic version of a hydrogen tank that could be used in the future in a short to medium range aircraft. Five filling levels, corresponding to a third to two thirds full tank, are examined. The reference tank geometry is also configured with two different baffle options in order to investigate the influence of the baffles as anti-sloshing device on the forces and oscillations using the three different versions. Furthermore, it is investigated how the longitudinal forces generated by the sloshing fuel differ depending on the fill level and the load case. Three load cases are investigated. First a simplified take-off abort, then an equally simplified pull-up and push-down maneuver of a realistic aircraft, and finally the acceleration that can occur in the tail area during a lateral gust, are examined.