Study on Impact Process of a Large LNG Tank Container for Trains

Abstract

In this paper, the impact process of a large LNG tank container for trains was studied by performing experiments and numerical simulations. Impact force with induced stress and deformation on the container especially on the frame was investigated and LNG sloshing inside the container was simulated. Experimental results show that for the initial velocity of 6.1 km/h, the maximum compressive stress is −366.3 MPa occurring on the longitudinal beam near the impact side corner fittings. The impact force produced by the transport vehicle is influenced by both the initial clearance and initial velocity, i.e., its maximum value increases with the clearance or velocity, which in turn directly affects the LNG impact force on the head, the tank container axial acceleration at the mass center and the frame deformation and stress distribution. The largest average pressure brought on by the LNG impact force is 8.83% of the design pressure, the inner vessel should be designed with a thickness allowance. When the initial velocity is 8 km/h, the ratio of the maximum LNG impact force to the static inertia force at each clearance is less than 0.23, which means that the calculation method of LNG static inertia force is conservative. In addition, the maximum axial acceleration of the tank container can reach 63 m/s2, greater than 4g inertial acceleration specified in the container design standard, meaning if assessed by the impact, the specifications of the standard are not conservative.