摘要
采用大涡模拟(LES)和标准κ-ε模型求解风力机近尾迹区域的非定常流动,获得涡量场信息和声源项信息,采用快速傅里叶变换将源项的时域信息转换为频域信息,利用K-FWH声学模型预测其噪声特性。结果表明,风轮在旋转过程中,风力机风轮下游同一截面在不同尖速比下涡量分布规律是从计算截面中心沿半径增大的方向分别经过3个压力脉动变化强烈的区域,它们是计算圆心区域、中心涡区域、叶尖涡区域,计算点在上述3个区域都会出现涡量的峰值;在同一尖速比不同截面下,风轮近尾迹区域涡量的变化规律是沿着X轴正方向远离风轮旋转平面计算截面上的中心涡区域和叶尖涡区域的半径增大,不断向外迁移;计算截面的最大声压级的数值计算值和试验值吻合较好,证明了噪声计算模型的正确性。
The unsteady flows of wind turbine near wake region were solved by the large eddy simula- tion （LES） and the standard model. The vorticity field information and source information were ob- tained. The time domain information of source was transformed into frequency domain information with fast Fourier transform. The noise characteristics were predicted using the K-FWH model. The results showed that during turbine rotation, at same cross section of the different tip speed ratio, the noise dis- tribution pattern of vorticity was three strong pressure fluctuation regions appearing from center of computation section to radius direction, which are computation center region, center vortex region and tip vortex region separately. There was a vorticity sharp peak in each region. At different cross section of the same tip speed ratio, the vorticity variation of wind turbine near wake is that the radius of center vortex and radius of tip vortex increase and constant migrate along the x axis positive direction away from the test section of the wind turbine. Calculation values and test values of the maximum sound pres- sure are in good agreement. It proved the correctness of the noise calculation model.
出处
《可再生能源》
CAS
北大核心
2013年第8期41-44,共4页
Renewable Energy Resources
基金
新疆教育厅高校科研计划项目(XJEDU2011S43)
新疆工程学院博士科研启动基金项目
