利用分区ALE算法数值模拟圆柱湍流涡致振动

Numerical simulation of turbulent vortex induced vibration of a circular cylinder adopted ALE domain decomposition method

用分区算法结合任意拉格朗日-欧拉法(ALE)数值模拟了圆柱湍流涡致振动。求解基于非交错网格系统,压力求解采用压力泊松方程提法,湍流模型采用标准k-ε模型和重整化群(RNG)k-ε模型。计算取中等雷诺数Re=5000、10000、15000、25000、50000等,质量系数M=10,阻尼系数ζ=0.00331,自振频率fn=0.18315、0.1628。计算结果表明:湍流涡致振动下圆柱时均阻力系数大于孤立圆柱绕流,而升力系数(振幅)值都小于孤立圆柱绕流。随着雷诺数增大,湍流粘性系数随之增大,但湍动能和湍流耗散率变化趋势不明显。对孤立圆柱绕流,研究结果与前人实验结果基本相符。

The turbulent vortex induced vibrations of a.circular cylinder were simulated. The flow was predicted to be turbulent,and was solved by the ALE domain decomposition method,in which the Poisson pressure equation formation was adopted. The standard κ-ε model and RNG κ-ε model were employed for turbulence. In this study, the Reynolds number was from Re=5000 to 50000, the non-dimensional mass coefficient was 10, damping coefficient was 0. 00331,and the natural frequency of the cylinder was 0. 18315 or 0. 1628. The results showed that the time averaged drag coefficients of the cylinder was larger than that of the stationary cylinder,while the amplitude of the lift coefficients was less than that of the stationary one. The turbulent viscosities increased with Reynolds number obviously, while the kinetic energy and dissipation were not obvious. The results compared essentially with previous experiments for flow around circular cylinder.