Experimental and numerical analysis of liquid sloshing within tank subjected to pitching motion

Liquid sloshing in partially filled tanks can generate large free surface oscillations, especially under pitch excitation. While extensive research has addressed sloshing in rigid containers, few studies focus on sloshing within flexible tanks or pure pitch-induced sloshing. This work presents a combined experimental and numerical investigation of sloshing dynamics in rigid and flexible tanks subjected to controlled pitch excitation. Many excitation configurations are considered. The numerical and experimental results are in close agreement in terms of oscillation frequencies, phase evolution, and response amplitudes. Only very small deviations are observed near the response minima, which may be attributed to limitations of the optical measurement technique. A parametric study investigates the effects of filling level and wave period on liquid sloshing. Finally, the study on flexible tank indicates that flexibility reduces sloshing amplitude.