Simulation Of FLNG’s Motion And Response Of FLNG’s Substructure

To satisfy the need of exloring offshore gas field, many researches pay attentions to a new type offshore structure, floating liquified natural gas (FLNG). FLNG keeps in service at a offshore gas field beyond20years in general, the motion of FLNG must be investigated to evaluate the stability of itself and its substructure’s safety in the design of FLNG. The characteristics of FLNG’s motion and motion response of FLNG’s substructures are studied through numerical simulation and model test in this thesis.At first, three dimensional motions of FLNG in different sea conditons are analyzed by numerical simulation. According to the FLNG’s motion, the method is proposed to guide how to take model test of motion response of FLNG’s substructure, and the design prameters of the six-degree-of-freedom test rig are proposed to simulate the motion of FLNG. As a example of substructure’s responses, the liquid sloshing in FLNG tank is analyzed. The functions, substuctures of FLNG and the problems in design and manufacture of FLNG are presented in the first chapter. In the second chapter, the motions of FLNG are simulated by AWQA software. In the third chapter, the method is proposed to conduct model tests of motion response of FLNG’s substructures and the parameters are given to design the test rig. In the fourth chapter, the liquid sloshing in rectangular tank and FLNG tank are analyzed by numerical simulation to obtain the phenomenon of liquid sloshing and distribution of sloshing load sloshing. The influence of amplitude and frequency of FLNG’ s motion on sloshing loads are also investigated by the numerical simulation and model test.