Numerical Simulation Of Fluid-Structure Interaction Of LNG Prestressed Storage Tank Under Seismic Influence

With the continuous growth of energy consumption, the level of demand of the natural gas which is clean energy is increasing sharply in the world wide energy market. Meanwhile, the structure of LNG prestressed storage tank is widely used, and the analysis of considering hydrodynamic interaction between LNG and tank have been the focus. Four aspects about numerical simulation of fluid-structure interaction of LNG prestressed storage tank under seismic influence were done.(1) Reference projects, the finite element model of LNG 50000m3 prestressed storage tank has been created by using ABAQUS software, meanwhile the 3-D models of rebar and LNG are created too. The prestress has been applied to the model of rebar with falling temperature method. Internal forces of LNG prestressed storage tank under hydrostatic pressure are calculated and analyzed, which prove that the falling temperature method for applying prestress is available, besides the maximum value of stress and displacement of cylinder are obtained and located, which are numerical and theoretical reference for analysis of fluid-structure interaction tank under seismic influence.(2) The fiber beam element of reinforced concrete so-called "equivalent section fiber beam concrete element" in ABAQUS has been researched. Models of specimens and complex structures of reinforced concrete, steel tube concrete and SRC can be created by this fiber beam element model, and the rebar ratio can be adjusted. The modeling technology of equivalent section beam can overcome the difficulty which the rebar in beam can only be used in static analysis, and the fiber beam element can be applied to dynamic explicit history analysis and save lots of elements.(3) The 3-D model of materiel with discrete behavior is created by using Arbitrary Lagrangian-Eulerian adaptive meshing analysis (ALE). Distributions of stress and displacement of a ball-mill system under conditions of working order and start-up have been calculated. The practice of ALE is powerful theoretical and practical reference for researching fluid-structure interaction by using the coupled Eulerian-Lagrangian analysis technique (CEL).(4) Dynamic behaviors of LNG under seismic waves of El Centro and Taft have been simulated by using CEL analysis technology, and hydrodynamic interaction between LNG and tank has been considered. Meanwhile, time history curves of displacement, acceleration and stress have been carried out and comparative analyzed. The conclusions indicate that analysis of fluid-structure interaction of LNG prestressed storage tank under seismic influence by using CEL analysis technology is available and reasonable.