复合材料立管涡激振动数值计算

基于尺度自适应模拟(SAS)和计算结构力学(CSD),对复合材料海洋热塑性增强立管(Reinforced Thermoplastic Pipe,RTP)涡激振动响应进行数值计算.数值计算了聚氯乙烯(PVC)立管涡激振动响应和复合材料层合板模态,并与实验数据对比,验证了文中双向流固耦合方法和复合材料建模的准确性.并且,分别计算了不同条件下的RTP立管和相同尺寸的钢制立管的涡激振动响应.计算结果表明:来流速度为0.1m/s时,RTP立管都发生了频率锁定现象;RTP立管的来流向振动响应和横向振动响应同样重要,不可忽略;来流向振动响应及流场三维效应导致立管中部区域振动响应的轨迹比较杂乱;来流速度为0.2m/s时,相同尺寸的钢制立管的来流向和横向振幅比RTP立管的小,且钢制立管主要是低阶模态振动;铰-铰约束情况下的RTP立管的振幅相比固定-固定约束情况下的整体上稍大,且主要是2、3阶振型运动.

Numerical Calculation of Vortex Induced Vibration of Composite Riser

Numerical calculation of vortex induced vibration (VIV) of reinforced thermoplastic pipe (RTP) based on scale adaptive simulation (SAS) and computational structure dynamics (CSD) is addressed. The VIV response of polyvinyl chloride (PVC) riser and the modal of composite plate are numerical calculated and compared with experiment data which verified the accuracy of two way fluidsolid coupling simulation and composite modeling method. Moreover, the VIV response of RTP and the same size steel riser in different conditions are calculated. The results show that the ‘lock in’ phenomenon occurrs when the free stream velocity equals 0.1m/s. The vibration response in incoming flow direction of RTP is as important as cross flow direction. The motion of the middle section of the RTP are in disorder due to the 3 dimensional effect of flow and the vibration of incoming flow direction. When the velocity is 0.2 m/s, the incoming flow and cross flow direction amplitudes of the steel riser are smaller than those of the RTP riser, and the steel riser mainly showed low order vibration. The amplitude of the RTP riser under hinge hinge constraint is slightly larger than that under the fixed fixed constraint, and it mainly showed switching motion of the second or third mode.