【摘要】 本文利用谱方法对光滑圆管内湍流流动进行了直接数值模拟 ,得到了圆管湍流充分发展的速度场和浓度场数据 ,利用DNS数据研究了圆管内湍流的低速条带、上抛、下扫等结构。通过求解浓度方程得到了浓度场数据 ,并对流动进行了显示。最后利用多种方法进行了猝发事件的检测 ,讨论了VITA方法中不同门限值对猝发检测的影响更多还原

【Abstract】 In this paper, the velocity field of fully developed turbulent pipe flow was obtained by the direct numerical simulation (DNS). Structures such as sweep, ejection, streak and burst were studied using these DNS data. The turbulent pipe flow was visualized by solving the concentration equation. The results are similar to those in experiments. Finally, several burst detection methods were used to detect burst event. The influence of the threshold values of k and τ in VITA method on the detection was discussed.更多还原