A buckling risk of oil storage tank under tsunami inundation was numerically investigated with Fluid–Structure Interaction (FSI) analysis. The fluid region of two–phase flow in tsunami was solved with a finite volume method solver based on VOF method and the solid region inside a storage tank model was solved with a finite element solver, and the field variables between the different regions were successfully exchanged without vast numerical cost. The developed simulation was applied to the problem for estimating tsunami and storage tank motion and the dependency of tank structural properties on buckling risk was investigated.
The Great East Japan Earthquake at 2011 caused heavy damages to Japan. When the earthquake occurred, a large tsunami was generated at Pacific Ocean, and the tsunami wave reached at Tohoku area in Japan. The tsunami inundation was widely observed at Tohoku area, and many peoples were injured and missed in this area. This tsunami wave only caused temporally flood disaster but triggered tsunami fire disaster due to oil spill. At the Kesennuma bay area in Miyagi prefecture, there were 23 oil storage tanks before the earthquake, then 22 tanks were broken and massive amounts of oil were flow out from the damaged tanks and wide fire disaster was caused at the tsunami inundation area (Zama, 2012). From this earthquake, tsunami fire disaster due to oil spill became to be known as a new risk when a large earthquake happens at countries with chemical complexes at bay area.
Japan is located at the position in which the probability of earthquake occurrence is very high. The Nankai Trough Earthquake assumes to be occurred in a few decades, many risk assessments for this earthquake are conducted based on numerical estimation. Tsunami simulation becomes a popular method for estimating inundation level and the detailed review for general tsunami calculation is not shown here.