Damage Simulation Of FPSO Structure Under Oil And Gas Leakage And Explosion

The exploration and exploitation of offshore oil and gas resources is the focus of China’s modern Marine strategy.With the development of oil and gas industry in China,Floating Production Storge and Offloading Units(FPSO)have been widely used in modern offshore oil and gas Production due to its advantages in economy and technology.The oil and gas treatment equipment of FPSO upper module is closely arranged,the process system is various,and the Marine environment is harsh,so it is very easy for oil and gas to leak and spread,forming combustible gas cloud,and further developing into serious explosion accident,which will harm the safety of construction personnel and damage the equipment structure.Based on the increasing development of offshore oil and gas exploitation industry in recent years,oil and gas leakage and explosion accident are constantly occurring.The analysis of oil and gas leakage and diffusion law of upper modules of FPSO and the dynamic response and damage characteristics of FPSO structure under explosion load are carried out to provide theoretical support and technical support for improving the safety,efficiency and control ability of FPSO operation.The main research contents of this thesis are as follows:(1)Analysis of FPSO oil and gas leakage and explosion accidentsThe process of oil and gas leakage and diffusion of the equipment and the distribution range of combustible gas cloud are analyzed numerically based on Fluent software.The process of oil and gas diffusion under different leak aperture,wind speed and wind direction is simulated,and the influence mechanism of each influencing factor on oil and gas leakage diffusion is discussed.And a cloud of combustible gas was obtained for the subsequent TNT equivalent explosion.(2)Analysis of FPSO leakage diffusion simulation processFLUENT software was used to analyze the oil and gas leakage diffusion process of the equipment and the distribution range of combustible gas cloud.The process of oil and gas diffusion under different leak aperture,wind speed and wind direction is simulated,and the influence mechanism of each influencing factor on oil and gas leakage diffusion is discussed.In addition,the cloud map of combustible gas was obtained to prepare for the subsequent TNT equivalent explosion.(3)Structural response analysis under FPSO explosive loadThe equivalent TNT method was used to determine the TNT equivalent of combustible gas cloud,The explosion numerical model was established and the explosion scene simulation and shock wave propagation process were carried out based on CFD method.The structural response of FPSO upper module equipment under the action of explosion was analyzed.The consequences of oil and gas leakage formed by different leak holes are compared,the shock wave load is compared,and the structural physical parameters,stress and elastic-plastic state are analyzed under different working conditions.(4)Risk Control ResearchIn view of the oil and gas leakage and explosion event of FPSO,based on the risk acceptance criteria,the implementation measures are put forward from the aspects of risk prevention,risk control and risk reduction,so as to reduce the probability of oil and gas leakage and explosion accident,reduce the scope of impact of the consequences,and better ensure the normal operation of FPSO.