针对不同长径比的有限长圆柱模型，采用大涡模拟及雷诺平均的方法，对高雷诺数下有限长圆柱绕流阻力特性进行数值模拟和分析，得到了圆柱阻力系数随长径比和雷诺数的变化规律，讨论端面效应对绕流阻力系数的影响。结果表明：在亚临界区内，相同雷诺数下阻力系数随长径比的增大而增大，呈线性变化规律，L/D的对阻力系数的影响明显大于Re对阻力系数的影响；在阻力危机区内，相同雷诺数下阻力系数随长径比的增大而增大，呈二次函数的变化规律，但各工况达到阻力系数“转折点”对应的雷诺数各不相同，基本呈现随雷诺数的增大向前推移的趋势，Re对阻力系数的影响明显大于L/D对阻力系数的影响；在阻力回升区，阻力系数回升的“转折点”随着雷诺数的逐渐增大而向后推移。在各分区内，端面效应对阻力系数的影响随雷诺数增大而更加明显，在高度方向上的最大影响区域约占圆柱总高度的16%。研究结果对有限长圆柱绕流特性的研究及应用具有重要意义和价值。
Large eddy simulation(LES) method and Reynolds average are applied to simulate drag characteristics at high Reynolds around finite circular cylinder, according to aspect ratio L/D. The Variation of drag coefficient with L/D and Reynolds number are taken. and the influence of the end face to the drag coefficient is also revealed. The results show that in the sub-critical region the drag coefficient has a linear change and increases with increase in L/D for the same Reynolds, additionally the influence of L/D to drag coefficient is large than the influence of Re; In the critical region the drag coefficient has a quadratic function change and increases with increase in L/D for the same Reynolds, and Re at turning point of drag coefficient under various conditions are different, additionally the influence of Re to drag coefficient is large than the influence of L/D; In the rise region the turning point of drag coefficient goes backwards with increase in Re. In each region the influence of the end face to the drag coefficient goes appreciably with increase in Re and the most effecting field is 16% in height of circular cylinder. Some meaningful references are provided for the further research on the characteristics of the flow around finite circular cylinder.
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