三峡升船机船-水-厢耦合系统的非线性有限元时域计算

Calculation of ship-water-chamber coupled system in the ship lift with finite element method in time domain

根据三峡升船机船厢的受力特点,在船厢的纵剖面上建立了非线性水波方程和船-水-厢的耦合运动方程。对非线性水波方程利用摄动理论进行分解得到一阶方程和二阶方程,然后运用伽辽金法得到耦合的有限元离散方程,结合精细积分法进行时域计算。计算采用平面八节点等参单元,并给出了若干算例。

A simplified ship-water-chamber model is developed in the load environment for the Three Gorge ship lift. Then the nonlinear water-wave equation of the fluid and the motion equation in the rigid structure are presented. After the nonlinear water-wave equation is expanded into the first and second order equations by the perturbation theory, the corresponding coupled finite element discrete governing equations have been derived by means of the Galerkin method and eight-node isoparametric element. The water-wave surface pressure and the general displacement of the rigid body are obtained with the precise integration. Two numerical examples are presented, in which the first is used in verifying the effectiveness of the method and the second shows us some practical results.