Structure Design Research On Marine Double-layer C-type LNG Storage Tank Based On ANSYS

With the rapid development of society and the improvement of energy demand,new requirements for green environmental protection have been put forward.It is urgent to promote low carbon life,to seek clean energy and to optimize the energy structure.Liquid natural gas(LNG)is a kind of clean energy with high calorific value and economy,which causes little pollution to the environment.The use of LNG power ships greatly reduces the water pollution and air pollution in the river area,reduces the fuel cost,and has a strong development potential.Therefore,it is of great value to analyze and study the double-deck C-type LNG storage tank.Based on the relevant design specifications,the main structures and accessories of LNG tank are designed and selected.Three dimensional model of storage tank is established.The strength of the main components of tank,outer tank,support structure and saddle are analyzed by using finite element method nder four ship navigation conditions,and the dangerous areas of the model is determined.The effects of internal pressure and liquid inertial force on the components are studied.Then,basing on the relevant codes of classification society,the calculation flow of fatigue cumulative damage is given.The fatigue cumulative damage degree of main components is obtained by formula calculation and finite element analysis,and the safety of main components of LNG storage tank is verified.Finally,the sloshing simulation of liquid medium is carried out through the CFX module of finite element software ANSYS,and the gas-liquid distribution of the tank and the static pressure change at the front head of the ship are studied under the condition of upward turbulence,which provides a reference for the safety design of the storage tank.The research on the safety of marine double-deck C-type LNG storage tank optimizes the design of the main components,which provides theoretical support for the wide use of LNG power vessels.In addition,the numerical calculation results under multiple working conditions also have some reference value for the design of other LNG tanks,which have practical significance in the safety of natural gas storage and transportation,and contribute to the further development of natural gas field in China.