摘要
从三维不可压缩雷诺时均Navier-Stokes方程出发,对90°弯曲管道内湍流流动进行数值模拟。网格划分采用六面体网格,湍流模型为RNGk-ε模型,在近壁区采用两层壁面模型进行修正,流场的计算结果与实验数据吻合较好。在此基础上,本文数值研究了来流方向对流场结构和流动特性的影响。得出在弯管流场中发生了分离现象,且随着来流侧滑角的增大,分离区范围增大。此外,随着来流从同一侧滑角变换至同一攻角时,横截面的二次流图像中也从具有两个对称主涡变成只具有一个主涡的现象。
On the basis of the Reynolds-averaged Navier-Stokes equations, the 3-D turbulent flow within 90° bending duct of square section was simulated numerically. The grid setting was hexahedron mesh, and the RNG k-ε turbulent model was utilized. The computed results are in good agreement with experimental data by treatment of two-layer model for the near-wall region. Furthermore, the influence of fluid motion directions on the flowfield and the flow characteristics were analyzed numerically. It is shown that the separation phenomena takes place in flowfield, and with the increase of sideslip angles, the magnitude of separation region increases. Moreover, with the fluid motion directions changing from attack angles to sideslip angles, a couple of main vortices are replaced by one main vortex in the secondary flow profiles of cross section.
出处
《计算力学学报》
CAS
CSCD
北大核心
2004年第3期314-321,329,共9页
Chinese Journal of Computational Mechanics
基金
教育部青年教师教学科研奖励基金
上海市曙光计划项目及上海市重点学科资助项目.
