复合式筒型基础波浪荷载特性研究

发布时间：2018-03-25 04:27

本文选题：复合式筒形基础　切入点：海上风电　出处：《天津大学》2014年硕士论文

【摘要】：风能资源具有高效和环保的优点，现已成为许多国家开发和利用的重要能源。海上风力资源是陆地风力资源的5倍，所以风电正在向海上发展。海上风机的基础矗立于复杂的海洋环境中，准确计算基础上所受波浪荷载尤为关键。本文基于线性绕射理论改进了MacCamy-Fuchs公式，使之适用于复合式筒型基础计算，并设立了四组规则波工况，分别通过Flow-3D数值波浪水槽模拟和物理水槽模型试验对改进公式的计算结果进行了验证。本文的主要内容和结论如下：（1）基于线性绕射理论改进并推导了适用于大尺度结构物上的波浪荷载计算公式。新公式将原公式中的定值半径r改为沿水深改变的函数R z，并简化了边界条件。在规则线性波浪作用下，改进公式计算结果与规则结构物上波浪荷载计算结果规律相符合，，计算荷载大小比前人使用莫里森公式计算出的结果略大。（2）利用计算流体动力学软件Flow3D建立了波浪和建筑物相互作用的三维数值水槽模型，模型采用规则造波边界造波，孔隙质结合出流边界进行消波。文本在数值水槽模拟中验证了天津大学李世森提出的在垂向孔隙率取为0.8，横向和纵向孔隙率取为0.9时，能有效减小出流边界的波浪反射的结论，并计算出了波浪荷载。数值计算结果与改进公式计算结果比较相差在3%-9%。（3）在物理水槽中，设立了波浪模型试验。在按照几何比尺制作的风机基础模型上安装了25只点脉压传感器对基础上的波浪荷载进行测量。文本利用平面上的点面转化系数公式，得到了复合式筒型基础在不同波浪荷载下的点面转化系数，取值范围为0.75-0.85。物理模型测试结果与改进公式计算结果比较相差在1%-10%，与数值计算结果比较相差在1%-9%。此结论充分验证了改进公式的准确性，并可以为海上风机基础设计提供一定的参考。
[Abstract]:Wind energy, which has the advantages of high efficiency and environmental protection, has become an important source of energy for development and utilization in many countries. So wind power is developing to the sea. The foundation of offshore fan stands in complex marine environment. It is very important to calculate wave load on the basis of accurate calculation. In this paper, the MacCamy-Fuchs formula is improved based on linear diffraction theory. It is suitable for the calculation of composite cylindrical foundation, and four sets of regular wave conditions are established. The calculation results of the improved formula are verified by Flow-3D numerical wave flume simulation and physical flume model test respectively. The main contents and conclusions of this paper are as follows:. 1) based on the theory of linear diffraction, the formula for calculating wave loads on large scale structures is derived. The new formula changes the constant radius r of the original formula to the function R z, which changes along the depth of water, and simplifies the boundary conditions. Under regular linear waves, The calculated results of the improved formula are consistent with the results of wave loads on regular structures, and the calculated loads are slightly larger than those calculated by previous researchers using Morrison's formula. (2) using the computational fluid dynamics software Flow3D, a three-dimensional numerical water tank model of wave and building interaction is established. The model uses regular wave boundary to generate waves. In the numerical flume simulation of Tianjin University, Li Shisen's conclusion that the vertical porosity is 0.8 and the transverse and longitudinal porosity is 0.9 can effectively reduce the wave reflection at the outlet boundary. The wave loads are calculated. The difference between the numerical results and the results of the improved formula is between 3 and 9. A wave model test was established in the physical flume. 25 point pulse pressure sensors were installed to measure the wave load on the fan foundation model made according to the geometric scale. The point and surface conversion coefficients of composite cylindrical foundation under different wave loads are obtained. The range of values is 0.75-0.85.The difference between the results of the physical model test and the calculation of the improved formula is 1- 10, and the difference between the results of the physical model and the numerical calculation is 1- 9.This conclusion fully verifies the accuracy of the improved formula. And it can provide some reference for the foundation design of offshore fan.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：P731.2;P742

【参考文献】