Numerical and Experimental Study on the Nonlinear Liquid Sloshing in Cassini Tank

Liquid sloshing within propellant tanks of space vehicles has been a major concern in aerospace engineering. The aim of the work in this paper is to develop a flexible computational framework with high precision to simulate three-dimensional large-amplitude liquid sloshing in Cassini tanks. The finite element method is adopted to solve the fluid equations of motion in an arbitrary Lagrangian–Eulerian (ALE) framework, where the characteristic-based split method is combined with a fractional step method for solving the control equations in which the ALE kinematic description is incorporated to track the free liquid surface flexibly and effectively for large-amplitude liquid sloshing in Cassini tanks. In addition, an experimental platform is set up to verify the reliability and effectiveness of the presented method. The numerical results obtained from computer programming by using the ALE finite element method proposed in this paper are compared with the experimental results, proving the model to be successful. The nonlinear phenomena of large-amplitude liquid sloshing, especially rotary sloshing (steady-state swirling and non-steady-state swirling), in Cassini tanks under horizontal harmonic excitation are investigated by both the ground physical experiments and numerical simulations.