Research On Storage Characteristics Of Marine LNG Tank

LNG as a clean, convenient and efficient energy, with its environmental protection, high heat value, convenient transportation and other advantages of the human society has become one of the high quality energy, especially in recent years, with the global LNG production and trade is becoming more active, liquefied natural gas industry is becoming one of the fastest growing energy industry. Due to the thermal insulation performance, the heat generated by the wall is bound to affect the temperature field and pressure field of the LNG fluid in the storage tank,The change of the internal pressure of the storage tank not only affects the economic benefit of transportation, but also the high gas pressure can also cause the safety hazard to the safety of the ship. Therefore, in order to obtain the heat transfer of the fluid in the LNG storage tank, the heat transfer law of the fluid flow in the tank is very important for the safe storage and transportation of LNG.This paper first introduces the background and significance of the research, reviews the research status of the low temperature liquid storage at home and abroad, and summarizes the various physical parameters of methane by using the method of polynomial fitting. And then taking the 1000m3 Marine LNG tank as the research object, according to the characteristics of this type of storage tank, the physical model is simplified, and the related hypothesis is put forward. The physical model and mathematical model of the thermal response of LNG storage tank are established, and the response process of LNG is simulated by using FLUENT software. K-e Realizable turbulence model is used to describe the fluid turbulent flow, and the VOF model is used to process the two-phase flow. The UDS model is used to establish the evaporation model program, and the source phase is added to the mass equation and energy equation. The flow field information, such as velocity, temperature, pressure and so on, is used to analyze the characteristics of flow and heat transfer in LNG storage tank, which can be used to design and improve the LNG storage tank. At the same time, the use of thermodynamic model calculation method for LNG storage tank storage process is calculated, and the thermal response of the tank simulation results and thermodynamic model calculation results are compared and analyzed, and the applicability of the assumption conditions of several thermodynamic models are discussed and analyzed, which is provides a reference for the selection of the traditional thermodynamic calculation model in engineering design.