(137c) Experimental Study and CFD Simulation on Bund Overtopping in Case of a Catastrophic Failure of Tanks Containing Water/Liquid Nitrogen/LNG

Storage tank integrity is critical for process safety. However, the integrity of a secondary containment in case of a catastrophic tank failure, especially a LNG tank failure, has been paid less attentions. Although there are already some available standards/regulations or good industrial practices on the design of a dike to contain the spilled liquid, there is few or no special considerations on the design of a dike for cryogenic liquid like LNG.

Overtopping is one of the major scenarios on loss of integrity of secondary containment. Previous studies have been performed on overtopping by several research groups all over the world. However, all of these works used non-cryogenic liquids, mainly water, to study the overtopping fraction. Very few of these efforts have been directed to extrapolate these data to other non-cryogenic liquids or cryogenic liquids, specifically LNG. For cryogenic liquids, the bubbles generated during the pool spreading process may change the bulk density, the liquid level or even the spreading process, which is critical to determine the overtopping fraction.

In this work, a series of lab-scale experiments will be performed to evaluate the overtopping fraction during a catastrophic tank failure. Effects of different liquids (i.e., water and liquid nitrogen) as well as geometries of dike and tanks will be studied. Then, a CFD-approach overtopping model will be created based on the lab-scale tests and be validated. The validated proposed model will be extrapolated to simulate the overtopping of an LNG tank failure in a real-world scenario.