CFD and Experimental Study on the Orifice Flow Characteristic of LNG through Crack in Insulation Panel

초록

For LNG carriers installing independent-type insulation tanks, it is mandatory to be able to store the leaked NG for 15 days after the leakage incidents through cracks or holes in the insulation structure. To ensure the safety requirement of LNG leakage incidents, it is required to predict the amount of NG spilling from the cracked holes of insulation panel. The CFD model of flow rate in LNG leakage is discussed in this paper. The CFD model is made to simulate the leakage of a LNG tank in the LNG storage. In order to validate the prediction method of LNG leaks, the leakage characteristics of liquid cargo were examined through experiments and the feasibility of prediction method was examined by combining it with numerical analysis. Experiments were carried out on the pressure conditions that can be generated in operation conditions on the LNG tanks by preparing a dedicated pressure vessel for the leakage experiment. The results show that the distribution of the outflow amount according to the crack shape was examined. Also, the numerical simulation model was created using the measured leakage flow from the experiment, and the leakage from the independent LNG tank was calculated by CFD analysis.