Analysis Of Stresses And Displacement Impacted By Lateral Fluid Dynamic Action For Vertical Pipeline

With the fact that mineral resources on the earth are reduced gradually,human hasdiverted their attention to the rich undersea minera resources.Since1972,developed countriesstarted to research on deep sea mining and technology and it gets mature day byday.However,sea mining technology in China is still at experimental stage and has not evertaken any sea trials.The subsystem of lifting pipe is a major part in deap sea miningsystem,which is also the key to the subsystem of lifting pipe.It influences thesafety, efficiency of collecting and stability of controlling of the whole system directly.The topic for the lifting pipe in the ocean mining ship connections and differentthickness of the stress and displacement is calculated and analyzed. the main research asfollows:（1）By lifting pipe stress analysis, to derive the solid-liquid coupled equations of thepipeline, establish the corresponding mathematical model（2）The section I pipe of lifting pipe fluid-structure interaction simulation model basedon the ADINA simulation software to build, complete stress analysis of different connectionmethods and different wall thickness when the lifting pipe working in seawater. From thesimulation analysis of the two connections, lifting hard pipe stress increases with the increaseof the external flow field relative velocity, stress changes are concentrated in the pipeline thetop of connections. Fixed type of lifting hard pipe with the increase of the external flowvelocity increases, the growth rate faster than articulated.(3) Ball joints should be used between the lifting pipe and the mining ship, Heavecompensation equipment should allow a certain degree of lateral and vertical rotation. Foundfrom the simulation and analysis of different thickness, with increasing pipe wall thickness,pipes of maximum and minimum stress is reduced accordingly, and with the increased stressreduces the amount of wall thickness less and less.(4) Establish the fluid-structure interaction model and complete when lifting pipeworking in seawater of different connection methods and analysis of different wall thicknessof displacement. From the simulation calculation found the offset of lifting pipe connected tothe mining ship has little effect on solid and articulated two connections, but relative speed oflifting pipe and water offset has a very great impact. With lifting hard tube thickness increases, x axis and y axis minimum and maximum displacement is reduced, and by increasing the wallthickness reduces the amount of displacement is getting smaller.