不同雷诺数下倾斜圆柱绕流三维数值模拟研究

基于计算流体力学(CFD)开源代码OpenFOAM开展了不同雷诺数(Re=100、1500和3900)和倾斜角度(-60°≤α≤60°)工况下倾斜圆柱绕流流场的三维数值模拟,研究倾斜圆柱绕流的三维瞬时及时均尾流流场、流线拓扑、升阻力系数与旋涡脱落频率随雷诺数及倾斜角度变化的规律,探讨在顺流向及逆流向情况下独立性原则对倾斜圆柱绕流的适用性。研究结果表明:随着圆柱倾角的增大,倾斜圆柱尾流产生较为明显的轴向流,尾流旋涡脱落受到明显抑制,细碎旋涡逐渐消失,尾流宽度随之减小;随着雷诺数的增大,圆柱尾流涡管发生明显的变形,展向掺混使得大量细碎旋涡产生,呈现出明显的三维特性。在不同雷诺数下,阻力系数均值、升力系数均方根及无量纲涡脱频率在一定倾角范围内符合独立性原则。

Three-dimensional numerical simulation on flow past an inclined circular cylinder at different Reynolds numbers

Three-dimensional numerical simulations are performed to investigate flow past a single inclined cylinder at different Reynolds numbers(Re=100,1500 and 3900)and inclined angles(-60°≤α≤60°)based on the computational fluid dynamics(CFD)open source code OpenFOAM.The three-dimensional instantaneous and time-averaged wake flow patterns,streamline topology,force coefficients and vortex shedding frequencies are analyzed.The validations of the Independence Principle on flow past an inclined cylinder in both forward and backward directions are verified,respectively.The results show that the vortex shedding is gradually suppressed with increasing of the inclined angle due to the effect of axial flow,and with increasing of Reynolds number,the vortex tube is obviously deformed.For different Reynolds numbers,the mean drag coefficient,root mean square lift coefficient and non-dimensional vortex shedding frequencies are in accordance with the Independence Principle in a certain range of the inclined angles.