大型LNG储罐泄漏扩散研究进展

大型LNG 储罐一旦发生泄漏,将会对周边人员和财产构成重大威胁。基于充分调研,分别从理论、试验及数值模拟3 个方面论述了国内外关于LNG 泄漏扩散的研究进展,尤其是近年来国内外在数值模拟方面的突破性研究成果。大型LNG 储罐泄漏后的气体扩散理论模型主要有高斯模型、唯象模型、箱及相似模型、浅层模型;通过LNG 泄漏试验获取了大量基础数据,主要包括气象条件参数、气云、液池燃烧的相关数据;在数值模拟方面,对LNG 泄漏气云扩散开展了大量研究,尤其是针对不同影响因素耦合作用下LNG 的泄漏扩散演变过程、气云变化形态、影响区域、爆炸范围等进行了模拟分析。通过对比分析发现,数值模拟方法具有成本低、精度高、可操性强等优点,既能有效拓展理论和试验研究成果,又能开展复杂工况下LNG 泄漏扩散的研究。对3 种方法的研究趋势进行了预测,提出大型LNG 储罐泄漏扩散的研究还需与接收站实际情况相结合,指出在今后的研究中应以数值模拟研究为主、试验与理论研究为辅。

Research progress on leakage and diffusion of large-scale LNG storage tank

Once leakage happens at a large-scale LNG storage tank, it will threaten personal and property security seriously around it. The domestic and foreign research progress related to LNG leakage and diffusion was described from the aspects of theory, experiment and numerical simulation based on the sufficient investigation, and especially breakthrough research achievements on the numerical simulation in recent years were expounded. It is shown that the theoretical models for the gas diffusion formed after the leakage of large-scale LNG storage tank mainly include Gauss model, phenomenological model, box and similarity model, and shallow model. LNG leakage experiments provide a great number of basic data, including meteorological parameters, gas cloud and liquid pool combustion. And in term of numerical simulation, extensive researches are carried out on the diffusion of LNG leakage gas cloud, and particularly the evolution process of LNG leakage diffusion, the morphological change of gas cloud, the influential area and the explosion range are simulated and analyzed under the coupling effect of different influential factors. Then, three kinds of methods were comparatively analyzed. It is indicated that numerical simulation method is advantageous with low cost, high accuracy and strong operability, and it can not only expand theoretical and experimental research results effectively, but also be used to study the LNG leakage diffusion under complex working conditions. The research trends of the 3 methods were predicted. It is suggested that the research on leakage and diffusion of large-scale LNG storage tank at home and abroad needs to be combined with the actual situation. Future research should use numerical simulation as a dominant method, and experimental and theoretical research as an auxiliary one.