Flow Induced Vibration And Buckling Analysis Of Pipe Strings In Gas Storage Wells

Gas storage injection-production string in the process of operation will be affected by gravity,the role of inside and outside temperature,pressure,and injection-production string in the casing,under the action of injection-production string will produce buckling deformation,injection-production string in the process of running at the same time,due to high temperature and high pressure fluid flow in a pipe string,can produce fluid-structure interaction and injection-production string vibration phenomenon easy to cause the injection-production string.In order to avoid the vibration of the injection and production string,the natural frequency of the injection and production string and the natural frequency of the fluid-solid coupling were analyzed,and the buckling phenomenon of the injection and production string under the action of fluid-solid coupling was studied.In this paper,the geometric and contact nonlinear finite element models of the injection and production string in the casing were established by using the finite element analysis method.In this paper,the influence of turbulent flow on the vibration of the injection-production string is analyzed,and the modal analysis of the injection-production string is carried out by using computational modal analysis method,and the natural frequency of the injectionproduction string is analyzed by considering the fluid-solid interaction between the injectionproduction string and gas.Considering the stress of the injection-production string in the wellbore,the natural frequency of the injection-production string under axial load and the natural frequency of the injection-production string under axial load and considering the fluidstructure coupling are studied.The results show that the natural frequency of the string decreases with the increase of the string length.Natural Frequency The natural frequency of the string decreases under axial load.When fluid-structure coupling is considered,the natural frequency of the injection-production string decreases,but gas-structure coupling has little effect on the natural frequency.Based on the known formulas of buckling critical length and buckling critical load,the critical load under certain buckling critical length is obtained by dynamic relaxation method.And fluid-structure interaction has been established finite element analysis of injectionproduction string and gas fluid-structure interaction effect on the string buckling critical length,research shows that when the injection-production string when considering the effect of pipe flow,when the pipe string buckling critical length for the fixed value,due to the effect of fluidstructure coupling of the fluid,injection-production string buckling critical length decreased,with the increase of flow rate,pipe string buckling critical length decreases the more;When the flow in the string is constant,the smaller the inner diameter of the string is,the more the critical buckling length of the string decreases.By studying the operation condition of the injectionproduction string in the gas storage,this paper studies the change of its natural frequency and the change of the critical buckling length,which has a certain guiding significance for the spacing of the injection-production string centralizer.