摘要
网格生成是复杂流动数值分析的重要组成部分,网格品质的好坏直接影响到数值解的获得和计算精度。对于汽轮机低压排汽缸和末两级耦合的流场来说,单块网格难以保证计算的准确性。为了更加透彻的认识排汽缸内三维流动的细节,利用多块网格技术生成了排汽通道分块结构化贴体网格,通过求解由RNGk-ε双方程湍流模型封闭的三维时均N-S方程对其进行了耦合数值分析,并采用混合平面方法处理末两级叶栅及其与排汽缸之间动静面的参数传递和相互干扰的问题,获得了排汽缸内部的压力和速度分布等重要流动信息。结果表明该方法能够预测出汽轮机排汽通道内部的流动特性,所得到的结果对排汽缸的优化设计具有重要的指导意义。
Mesh generation plays an important role in numerical analysis of complex flow. The quality of mesh has direct effect on the precision and convergence of numerical results. As the computational domain includes exhaust hood and last two stages, it is difficult to obtain precise results using the single-block grid, so the multi-block mesh is adopted to get the detailed three-dimensional flow in exhaust hood. By introduction of mixing plane approach and RNG κ-ε turbulence model, the reynolds averaged N-S equations are adopted to get detailed information of pressure and velocity in exhaust hood. The numerical results show the method developed in this study can analyze flow field of exhaust channel in detail and provide significant parameters for optimal design of exhaust hood in steam turbine.
出处
《汽轮机技术》
北大核心
2007年第4期246-249,共4页
Turbine Technology
基金
国家863高技术基金项目(2006AA04Z404)
关键词
汽轮机
数值分析
多块网格
排汽缸
steam turbine
numerical analysis
multi-block mesh
exhaust hood
