鹰式波浪能装置旋转碰撞的损伤分析

Damage Analysis of Eagle Wave Energy Converter in Rotating-Collision

基于鹰式装置实海况试验时限位梁被撞坏的案例及显式非线性有限元法,研究了限位梁的破坏机理,并改进了装置的限位方案。对鹰头吸波体与限位梁的碰撞过程进行了仿真分析,吸波体及限位梁分别采用刚体和弹塑性材料进行模拟,并考虑了吸波体及限位梁运动惯性的影响,获得了能量分布曲线、结构应力分布及变形图、撞击力-位移曲线等结果,仿真结果与限位梁实际损坏情况较吻合。调整了防撞块的材料类型和间距,分析可知,利用碰撞对吸波体进行限位容易使限位梁发生屈服失效;而通过增加蓄能器的使用容积来存储吸波体多余动能的方案可有效保护装置不被破坏。

The end beam on the Eagle wave energy converter （WEC） was broken up during the real sea experiment. To make clear the damage mechanism, the collision of the end beam and the wave energy absorber （WEA） was studied by the explicit nonlinear finite element analysis. In the simulation, the WEA was assumed as a rigid body, and the end beam an elastic-plastic structure. The inertia effects of WEA and the end beam were taken into account. Through the simulation, the structural stress and the deformation of the end beam were obtained. In addition, the energy absorption and the collision force were also investigated. The results fit well with the actual damage situation. We also simulated the impact of the device with different materials and intervals of bumper blocks on the WEC, and it was found that the beam was not strong enough to limit the motion of WEA. As a result, an improvement scheme of increasing the maximum volume of energy accumulator was presented to absorb the redundant kinetic energy of WEA.