海底管线铺设状态下的动力特性的有效数值方法

AN EFFICIENT NUMERICAL MODEL FOR THE DYNAMIC BEHAVIOR OF PIPELINE DURING LAYING

本文介绍质量集点数值方法在非线性、大位移及时域求解铺设状态下管线动力性性计算中的应用,尤其是其顶部和底部动边界的模拟,计算机程序可以在IBM-PC机上实现。 为检验数值计算的可靠程度,管线弯矩应力的模型试验在上海交通大学流体动力实验室完成,模型管线用PVC塑管模拟,几何比为1:25,取得了令人满意的试验结果,它证明数值计算是成功的。 本数值方法也可用作静力分析,并与有限差分数值静力计算进行比较,二者吻合较好。 管线铺设状态下的最大动弯矩力约为静态弯矩应力的1.2倍左右,这一现象应引起注意。

The numerical of the so-called lumped mass method which takes into consideration nonlinearity and large displacement and is in time domain, has been used for the dynamic analysis of pipeline during laying, especially for the simulation of the moved boundary conditions on the upper end and lower end of the pipeline. The computer program can be realized on a IBM-PC microcomputer.Model tests for validating the numerical model have been carried out in the ship nydrodynamic laboratory of Shanghai Jiaotong Univ. The pipeline model has been made from PVC pipe and at scale ofl : 25. The agreement of the results between the model tests and the numerical model is fairly good.The numerical model can also be used for the static analysis of pipeline during laying. It has been compared with the calculation of the finite differential techniques in static situation, which shows that the accuracy of the present numerical model is the same as that of the other numerical techniques.The maximum value of bending stresses in dynamic situation is about 20 percent higher than that of the static situation. This phenomenon should be paid to an adequate attention.