Calculating football drag profiles from simulated trajectories
Calculating football drag profiles from simulated trajectories
复制标题
根据模拟轨迹计算足球阻力曲线
DOI：
10.1007/s12283-013-0124-0
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发表时间：
2013
影响因子：
1.7
通讯作者：
S. Choppin
中科院分区：
文献类型：
--
作者：
S. Choppin
作为一个虚张声势的物体，由于早期的边界层分离和较大的低压区域，足球在层流流动时会经历很高的气动阻力。足球接缝的长度和深度可以通过在较低雷诺数下触发湍流边界层来影响分离点。足球制造商可以通过精心设计和材料选择来控制足球的行为。然而，评估足球的空气动力学性能可能是一个漫长且昂贵的过程，传统上需要使用合适的风洞。测量不同雷诺数下的阻力可以得到完整的空气动力学轮廓，从而确定球在飞行过程中的行为。一些研究尝试使用记录的轨迹来确定足球的空气动力学特性，但这些仅确定了平均特性，而不是完整的空气动力学特性。本文描述了一种使用一系列记录的轨迹来计算足球的完整空气动力学特性的方法。为了评估该方法的准确性和鲁棒性，使用了添加了不同程度的噪声和气动升力的模拟轨迹数据。评估发现随机噪声不会显着影响方法的准确性。在较大的幅度下，随机空气动力升力使该方法无效（相当于球旋转 >100 rpm）。未来的工作将集中于使用 3D 高速视频技术记录的球轨迹来评估该方法的有效性。
As a bluff object, a football experiences high aerodynamic drag when flow is laminar due to early boundary layer separation and a large low-pressure region. The length and depth of a football’s seams can influence the separation point by triggering a turbulent boundary layer at lower Reynolds numbers. Football manufacturers can control a football’s behaviour through careful design and material choice. However, assessing the aerodynamic performance of a football can be a lengthy and expensive process, traditionally requiring the use of a suitable wind tunnel. Measuring the drag force at varying Reynolds numbers gives a full aerodynamic profile which determines how the ball will behave during flight. Some studies have attempted to establish the aerodynamic properties of footballs using recorded trajectories, but these only ascertained average properties rather than a full aerodynamic profile. This paper describes a method which uses a series of recorded trajectories to calculate the full aerodynamic properties of a football. To assess the accuracy and robustness of this method, simulated trajectory data were used to which varying degrees of noise and aerodynamic lift were added. The assessment found that random noise does not affect the accuracy of the methodology significantly. At larger magnitudes, random aerodynamic lift makes the methodology ineffective (equivalent to ball spin >100 rpm). Future work will concentrate on assessing the effectiveness of the methodology using ball trajectories recorded using 3D high-speed video techniques.
影响因子：
1.7
作者：
Asai, T.;Seo, K.;Sakashita, R.
通讯作者：
Sakashita, R.