TEMPERATURE REDUCTION ON LNG BUNKERING SHIP STRUCTURE UNDER ACCIDENTAL CRYOGENIC GAS RELEASE USING CFD SIMULATION

Liquefied Natural Gas (LNG) fuel has been proven to minimize sulfur oxide, nitrogen oxide, and particulate matter emissions. LNG fuel becomes a good option to fulfill an alternative fuel demand in shipping industries. Consequently, LNG bunkering ships have to deploy in order to meet the LNG bunkering infrastructure demand. In the event of an accidental LNG release, the cryogenic exposure causes embrittlement of steel that leads to the ship's structural failure. The scope of this work is to establish accidental LNG release scenarios considering the leak and environment-related parameters, to observe the cryogenic flow and gas accumulation on the LNG bunkering ship's structure. The reservoir pressure, leak size, leak directions, leak positions, and release rates are provided as the leak-related parameter. A wind rose data of Ulsan Port (South Korea) is utilized to determine the wind speed, wind direction, and ambient temperature as the environment-related parameter. The release duration is set in 15 minutes which is the emergency shutdown valve reaction time. Kameleon FireEx (KFX) was employed to execute the LNG release simulation. The grid and iteration convergence tests were presented to ensure the current model's accuracy. Finally, the thermal footprints of structure and gas accumulation characteristics are discussed in this paper.