摘要
采用差分方法求解基于Boussinesq假设下三维不可压缩Navier-Stokes方程,直接数值模拟了底部加热、顶部冷却的竖直圆柱容器内Rayleigh-Bénard湍流对流问题,探讨了不同形参比下流场中大尺度环流结构、轴对称环状涡结构的变化规律,分析了形参比对于平均流场和湍流脉动统计量以及表征传热特性的Nusselt数的影响.
By means of a finite-difference scheme to solve the three-dimensional incompressible Navier- Stokes equations under Boussinesq assumption, direct numerical simulation was performed to study the turbulent Rayleigh-Benard convection in a vertical cylindrical container heated from below and cooled from above. Two typical large-scale structures of the mean flow were identified and discussed. One is the large recirculation cell and the other axisymmetric toroidal vortices. The influence of aspect ratio on the mean flow feature and some typical turbulence statistics were analyzed.
基金
国家自然科学基金(10772173)资助
