The objective of this work is to determine initial structural response from a blast threat for the newer class of liquefied natural gas (LNG) vessels. Import of LNG by ship is expected to significantly increase in the coming decade and there is concern over vulnerability. Current vessels hold up to 160,000 m3 of LNG, while the new vessels will hold up to 266,000 m3. These vessels are double-hulled and have an insulating containment system which keeps the LNG at a temperature of 111 K. Calculations were performed to determine the structural response of these ships from blast using CTH, a shock-physics code, developed at Sandia National Laboratories. The calculations were performed on massively parallel computing platforms (∼1000 processors) due to the number of elements required (∼109). Detailed geometry of the stiffeners, framing, and changing hull thickness with elevation were included, as well as the insulation, LNG, and water. Thus, there is multiphase interaction with the structure. The geometry of these ships fall within a class of problems termed ‘thin-walled problems’ since they require resolution of length scales from ∼10 mm to ∼10 m. In order to capture the smallest length scales an adaptive mesh refinement (AMR) feature was used. This feature allows for cells to be concentrated in active regions as the calculation progresses. This paper will discuss the resolution challenges of simulating thin-walled problems, as well as regimes in which shock-physics codes, such as CTH, are appropriate for application. Results will be provided without disclosure of threats.

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