To build a real-time dynamic deepwater pipe-laying visual simulation system, using the "Offshore Oil 201"pipelaying vessel as our research object, we considered the influences of ship motion, wave load, seawater load,and the dynamic positioning system on the pipeline and initial cable, and establish differential equations for the pipeline and cable dynamics.We used the beam theory to establish a pipeline vibration equation for analyzing the pipeline vibration characteristics.We used the differential quadrature method to determine boundary conditions for the differential equations and used the explicit difference method to iteratively obtain numerical solutions for the vibration equations.Then,we performed simulation experiments to analyze the pipeline shape under different sea conditions and behaviors as well as the action force at key pipeline locations.We analyzed the coupling system of the pipeline and cable and built a dynamic model of the initial pipe-laying simulation system in real time.The re-sults show that when the wave height increases from 2 m to 4 m,the maximum tension of the pipeline increases by 4.55 kN and the lateral displacement of the pipeline detachment point increases by 41%.Increased sea conditions and increased magnitude of the ship movement will exacerbate the vibration amplitude and vibration distance of a pipeline.We compared the simulation results with those of commercial software,and determined the error rate to be less than 4%.These results meet the accuracy requirements of the proposed simulation system.%为构建实时动态的深水铺管作业视景仿真系统,本文以"海洋石油201"铺管船为研究对象,考虑船舶运动、波浪载荷、海流载荷以及动力定位等对管线和初始缆的动态影响,建立了管道和缆索动态的微分方程组.利用梁理论,对管道振动特性进行分析,建立了管道振动方程.基于微分求积法确定微分方程组边界条件,利用显式差分法迭代获得振动方程数值解.通过仿真实验分析了不同海况、工况下管道的形态以及管道关键位置的作用力;对管道和缆索耦合系统进行分析,并构建了实时计算的初始铺管仿真系统的动态模型.研究结果表明:海况由2m浪高增加到4 m浪高时,管线最大张力增大了4.55 kN,管道脱离点横向位移增大了41%;海况和船舶运动幅度增大,会加剧管线的振动幅度和持续距离.将仿真结果与商业软件进行对比,误差率保持在4%以内,满足仿真系统的准确性要求.
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