# Study on Impact Process of a Large LNG Tank Container for Trains
## 1 Introduction  
Tank containers may frequently be impacted during railroad transit due to the operation of the train connection. Under impacts, the tank container's motion state changes, causing slosh of the internal liquid, which in turn will have an effect on the tank container. In extreme situations, the impact would cause significant deformation or possibly structural strength breakdown, leading to container leakage or even catastrophic disaster. The effect and sloshing of liquid-filled containers has been extensively researched. In order to describe the hydrodynamic damping provided by vertical and horizontal baffles in partially filled rectangular liquid tanks, [PERSON] et al. [1] conducted analytical solution approach and experimental investigations. In order to study the nonlinear behavior and damping characteristics of liquid sloshing, [PERSON] et al. [2] used a numerical algorithm based on the volume of fluid (VOF) method to simulate pressure variations and three-dimensional effects on liquid sloshing loads in a moving partially filled rectangular tank. [PERSON] et al. [3] studied the drop of liquid carrying water tank using ALE and other algorithms, and they discovered that ALE algorithm may qualitatively represent the test findings. [PERSON] et al. [4] examined the differences of various methods by setting up a numerical simulation of the collision between liquid-filled containers and container ships and discovered that the ALE method is more rational and reduces computation time. [PERSON] et al. [5] investigated the working medium sloshing in the oil tank after it impacted the ground using the ALE method and contrasted the effects of adding an anti-wave plate. In their study of the nonlinear oscillation in the container, [PERSON] et al. [6] discovered that the excitation frequency has an impact on wave height. [PERSON] et al. [7] studied the liquid sloshing in the rectangular tank, and then verified the numerical simulation resultswith experimental methods. In order to explore the liquid sloshing during braking, [PERSON] et al. [8] employed the VOF model. They also examined the stress on the tank container under various liquid filling ratios K and various wave plate areas. The work of numerical simulations regarding the dynamic behavior of the container under impact loading was given by [PERSON] et al. [9]. [PERSON] [10] discussed the nonlinear liquid sloshing dynamics under sway and rotational excitations for various container geometries, together with the dimensionless factors influencing the construction of small-scale models, and examined the liquid sloshing evaluation of liquefied natural gas tanks. The critical baffle height, at which liquid never reaches the tank's ceiling at any point, was discovered by [PERSON] et al. [11] after they numerically examined the impact of the vertical baffle height on the sloshing of liquid in a laterally moving 3D tank. Through a new approach based on the coupling strategy of smoothed finite element method (SFEM) and an enhanced version of smoothed particle hydrodynamics (SPH) delivering superior accuracy, [PERSON] et al. [12] computationally evaluated the sloshing mitigation utilizing elastic baffles. The numerical study by [PERSON] [13] compared two different numerical approaches that are both implemented in a research hydrocode: a pure Lagrangian discretization with Finite Elements (FE) and element erosion, and a coupled adaptive FE/SPH discretization. The study simulated projectile impacts on fluid-filled containers. In a partially filled laminated composite container, the non-linear motion of the liquid free surface caused by sloshing and the accompanying coupling caused by the fluid-structure interaction effect were the main topics of [PERSON] et al. [14]'s study. A straightforward equivalent mass-spring model developed by [PERSON] et al. [15] predicts the typical pulse duration and pressure distribution on the vessel walls throughout the impact test.