海洋石油立管的三向大位移分析

本文对截面具有两个不相等主惯性矩的海洋石油立管的三向大位移分析作了理论推导。在推导中,全面考虑了立管弯曲、扭转和拉伸变形。通过综合立管轴向的平衡条件和能量泛函的驻值条件,得出了独特的混合方法。平衡状态时立管中心线的孤长s取为自变量,而立管中心线的坐标X、Y和截面扭转角F以及管内拉力T则为孤长s的函数。在上述理论推导的基础上,形成了求解具有二相等主惯性矩的立管三向六位移分析的有限元方法。根据此方法编写了计算机程序,并给出了算例。

3-D Analysis of Marine Riser with Large Displacements

A formulation to analyse the large displacement problem of a marine riser with two unequal principal moments of inertia of the cross section in the 3-D space is presented.In the formulation,the equilibrium in the axial direction and the stationary condition of an energy functional are utilized to form a unique hybrid method.The torsional as well as the axial and bending deformations are all taken into account.The coordinates X and Y,twisting angle F,and the tension T are the four dependent variables, while the are length s in the equilibrium state is the independent variable. Based on the theoretical formulation mentioned above,a finite element method is developed to solve the large displacement problem of the riser with equal principal cross sectional moments of inertia in the 3-D space. A computer program is developed and a numerical example is given.