Parameters of horizontal nitrogen tank.

The changes in pressure, temperature, and filling rate inside LNG tank container are related to non-destructive storage time. In order to solve these problems, it was necessary to understand the distribution of temperature, pressure and evaporation in the LNG storage tank during transportation. The study on the relationship between the initial filling rate and safe storage time is still rare. Based on the principle of mass conservation and energy conservation, the pressure calculation model of the horizontal low-temperature LNG tank was established and verified by an experiment. A study was conducted on the LNG tank container in Golmud-Lhasa, and experimental data such as pressure changes in LNG tank containers during transportation were obtained. The storage calculation results obtained by the model were compared with the experimental data. The research results show that the simulated calculated values agree well with the experimental values, there was an “optimal initial filling rate” in the LNG tank. When the initial filling rate was less than the optimal initial filling rate, the safe storage time of the tank increases with the increase of the initial filling rate. When the initial filling rate was greater than the optimal initial filling rate, the safe storage time of the tank decreases with the increase of the initial filling rate.

液化天然气（LNG）罐式集装箱内部的压力、温度与充装率变化，与无损存储时长密切相关。为解决此类问题，需明晰运输过程中液化天然气储罐内温度、压力与蒸发分布情况。目前针对初始充装率与安全存储时长之间关联的研究仍较为匮乏。基于质量守恒与能量守恒原理，建立了卧式低温液化天然气储罐的压力计算模型，并通过实验对模型进行了验证。针对格尔木至拉萨线路的液化天然气罐式集装箱开展了研究，获取了运输过程中罐内压力变化等实验数据。将模型得到的存储计算结果与实验数据进行了对比。研究结果表明，模拟计算值与实验值吻合度极佳，液化天然气储罐存在“最优初始充装率”：当初始充装率低于该最优值时，储罐安全存储时长随初始充装率升高而延长；当初始充装率高于该最优值时，储罐安全存储时长随初始充装率升高而缩短。