Fatigue Analysis of a 40 ft LNG ISO Tank Container

Abstract

The demand for Liquefied natural gas (LNG) has rapidly increased over the past few years. This is because of increasingly stringent environmental regulations to curb harmful emissions from fossil fuels. LNG is one of the clean energy sources that has attracted a great deal of research. In the Republic of Korea, the use of LNG has been implemented in various sectors, including public transport buses, domestic applications, power generation, and in huge marine engines. Therefore, a proper, flexible, and safe transport system should be put in place to meet the high demand. In this work, finite element analysis (FEA) was performed on a domestically developed 40 ft ISO LNG tank using Ansys Mechanical software under low- and high-cycle conditions. The results showed that the fatigue damage factor for all the test cases was much lower than 1. The maximum principal stress generated in the 40 ft LNG ISO tank container did not exceed the yield strength of the calculated material (carbon steel). Maximum principal stress of 123.2 MPa and 107.61 MPa was obtained with low-cycle and high-cycle analysis, respectively, which is 50.28% less than the yield strength of carbon steel. The total number of cycles was greater than the total number of design cycles, and the 40 ft LNG ISO tank container was satisfied with a fatigue life of 20 years.

Comparative FEM Analysis of Vacuum and Perlite Insulation Techniques on the Structural Integrity of Independent Type C Liquefied Natural Gas Tank

“…The structural analysis follows heat transfer analysis, which is used not only to calculate stress due to thermal expansion but also to superimpose different loading cases: maximum acceleration due to maneuvering, 30 • healing condition, and collision condition. In a similar analysis performed by Lee et al [21], the tank was subjected to a superimposed load of pressure, acceleration, and weight. Wang and Quian [22] presented a structural analysis without thermal loads to evaluate how inertial forces and internal pressure deform parts of the LNG tank.…”

Design Improvement Using Topology Optimization for the Structural Frame Design of a 40 Ft LNG ISO Container Tank

“…Adding stiffness to the structure will reduce this structural strain energy, which can be achieved by assigning density to individual element units through design variables. The strain energy (U) formulation can be expressed in Equation (3).…”

“…LNG ISO tanks are containers used for transporting various gas products, liquids, and hazardous chemicals in large quantities safely and efficiently [3]. ISO tanks facilitate gas distribution to areas in Indonesia that still need to be connected to the gas pipeline network.…”