Research On The Deep-Sea PIP In Global Thermal Buckling Mechanism Under High Temperature And Pressure

With the increasing of human social demand for oil energy,land to sea has become the most important human choice.Offshore oil mining's strength increases gradually,the status of efficient deep-sea oil pipeline is increasingly important,and the lack of the pipe-in-pipe(PIP)'s global thermal buckling analysis,the main influence factors for the PIP are the non-uniform temperature field,the high pressure and the pipeline's initial imperfect.In this paper,the finite element analysis is on the influence factors of these three aspects,through comparing with the existing theoretical research and experimental study on this analysis,the main research work is as follows:1.Using the FLUENT software to simulate the crude oil in different thermal insulation medium to show the action of the temperature change along,by controlling the thickness of insulation and combining with the engineering practice,getting the accurate non-uniform temperature field,and by using the software of ABAQUS to study the insulation's structure effect.Eventually,getting the conclusions of the insulation in the process of PIP buckling almost have no structure affect,which benefits simplifying the finite element analysis of PIP buckling.2.Using the ABAQUS software,and the non-uniform temperature field of the last chapter,using ITT unit to set up the model of the PIP,research the deep-sea PIP's temperature effects of different high pressure,axial stress and axial displacement,get the performance of the PIP in different pipeline of high pressure field's distribution regularity of temperature effect.By introducing different initial imperfect,studying the lateral buckling of the PIP,using the parametric analysis to study the influence rules of different degree of initial imperfect on pipeline operation.3.With the existing experimental study and using the ABAQUS software,studying the initial imperfect of PIP's dynamic effect,Based on the dynamic effect in the whole thermal buckling test of PIP with initial imperfections,This paper analyzes the parameters about diameter,initial defect length and pipe-soil interaction affection on the PIP global buckling,and find out the relationship between the various factors.By analyzes the midpoint of pipeline buckling,lateral velocity,lateral displacement and popup kinetic energy,get the control method of a dynamic effect in subsea PIP.This paper researchs the PIP global thermal buckling in three main factors:getting a more accurate temperature field,studying the influence of deep-sea high pressure on the temperature effect of the PIP by means of parametric analysis;building the initial imperfect of PIP buckling model,putting forward the conclusions which are beneficial to the safe operation of the PIP,and having the value of engineering application.