不同雷诺数下的单一圆柱绕流流场分析

Analysis of Flow Field around a Single Cylinder at Different Reynolds Numbers

为了分析均匀流体流经圆柱发生体后产生的绕流流场特性,采用数值计算的方法,对不同雷诺数下的均匀来流流经圆柱体的流动过程进行数值计算,研究分析不同工况下流场的流动形态,得到了不同雷诺数流动状态下的流场参数变化规律谱及流经圆柱发生体时的流线谱,并对同一雷诺数下不同时刻的流场形态及静压力变化情况进行了分析。结果表明,流体流经圆柱发生体时的阻滞作用随雷诺数的变化而产生变化,流体惯性力随雷诺数的增大对流场的平衡状态产生的影响增大,流经圆柱发生体后的旋涡由旋向相反的对称分布逐渐发生扰动,且旋涡尺度逐渐增大;同时,受圆柱发生体阻滞作用及流体黏性的影响,在圆柱发生体迎流面受到的力作用最大,圆柱发生体上下对称分布位置的力作用基本一致,随着流动距离的增大,流场的静压力逐渐变小,流场变化趋于平缓。

In order to analyze the characteristics of the flow field around the cylinder when the uniform fluid flowed through the cylinder generating body,the flow process of the uniform flow through the cylinder under different Reynolds numbers was numerically calculated,the flow patterns under different working conditions were studied and analyzed,and the flow field parameter variation law spectrum under different Reynolds numbers and the flow pattern of the uniform flow through the cylinder were obtained.And the flow pattern at different time and the change of static pressure under the same Reynolds number were analyzed.The results showed that the retardation of fluid flowing through the cylinder body changed with the change of Reynolds number,and the inertial force of fluid increased with the increasing of Reynolds number,and the influence of the equilibrium state of convection field also increased.The symmetrically distributed vortex with opposite direction after flowing through the cylinder body were disturbed,and the vortex scale increased gradually.At the same time,with the influence of cylinder block and fluid viscosity,the force acting on the upstream of the cylinder was the largest,and the force acting on the symmetrical distribution position of the cylinder was equal.With the increasing of the flow distance,the static pressure of the flow field became smaller and the flow field changed more smoothly.