Hunting stability analysis of partially filled tank wagon on curved track using coupled CFD-MBD method

Abstract

In this study, we develop an innovative numerical method for the investigation of the stability of a partially filled tank wagon moving on a curved track. The calculations are carried out in two subsystems including a dynamic system and fluid sloshing. We analyze the wagon dynamic system the multibody dynamic (MBD) model with 21 degrees of freedom (21-DOFs), which takes into account the lateral, vertical, roll, pitch, and yaw motions. The heuristic creep theory is used for the wheel–rail contact model. We adopt the fourth-order Runge–Kutta method for solving of this model. The transient fluid slosh is simulated by the computational fluid dynamic (CFD) model. The volume of fluid (VOF) technique is used for tracking the free surface of the fluid. This model is validated experimentally using the sloshing test setup. Then the simultaneous interaction between the dynamic system and the transient fluid slosh is analyzed by coupling the CFD model with the MBD model. By the parametric study on the filled-volume and wagon velocity, the critical hunting speed is derived by the Lyapunov indirect method. The results show that a higher filled volume decreases the critical hunting speed. Also, at the instability condition, an increasing trend for the phase trajectory of the wagon components is evident.