Barbosa Tiago M, Ramos Rui, Silva António J, Marinho Daniel A
a Physical Education & Sports Science Academic Group, National Institute of Education , Nanyang Technological University , Singapore.
b Research Centre in Sports, Health and Human Development , Vila Real , Portugal.
J Sports Sci. 2018 Mar;36(5):492-498. doi: 10.1080/02640414.2017.1321774. Epub 2017 Apr 28.
The aim was to compare the passive drag-gliding underwater by a numerical simulation and an analytical procedure. An Olympic swimmer was scanned by computer tomography and modelled gliding at a 0.75-m depth in the streamlined position. Steady-state computer fluid dynamics (CFD) analyses were performed on Fluent. A set of analytical procedures was selected concurrently. Friction drag (D), pressure drag (D), total passive drag force (D) and drag coefficient (C) were computed between 1.3 and 2.5 m · s by both techniques. D ranged from 45.44 to 144.06 N with CFD, from 46.03 to 167.06 N with the analytical procedure (differences: from 1.28% to 13.77%). C ranged between 0.698 and 0.622 by CFD, 0.657 and 0.644 by analytical procedures (differences: 0.40-6.30%). Linear regression models showed a very high association for D plotted in absolute values (R = 0.98) and after log-log transformation (R = 0.99). The C also obtained a very high adjustment for both absolute (R = 0.97) and log-log plots (R = 0.97). The bias for the D was 8.37 N and 0.076 N after logarithmic transformation. D represented between 15.97% and 18.82% of the D by the CFD, 14.66% and 16.21% by the analytical procedures. Therefore, despite the bias, analytical procedures offer a feasible way of gathering insight on one's hydrodynamics characteristics.
目的是通过数值模拟和解析方法比较水下被动拖曳滑行。一名奥运游泳运动员通过计算机断层扫描进行扫描，并对其在流线型姿势下在0.75米深度处的滑行进行建模。在Fluent上进行稳态计算机流体动力学（CFD）分析。同时选择了一组解析方法。两种技术都计算了1.3至2.5米·秒之间的摩擦阻力（D）、压力阻力（D）、总被动阻力（D）和阻力系数（C）。CFD计算得出的D范围为45.44至144.06牛，解析方法计算得出的D范围为46.03至167.06牛（差异：1.28%至13.77%）。CFD计算得出的C范围在0.698至0.622之间，解析方法计算得出的C范围在0.657至0.644之间（差异：0.40 - 6.30%）。线性回归模型显示，以绝对值绘制的D具有非常高的相关性（R = 0.98），在对数 - 对数变换后（R = 0.99）也是如此。C在绝对值（R = 0.97）和对数 - 对数图（R = 0.97）中也都得到了非常高的拟合度。对数变换后D的偏差为8.37牛和0.076牛。解析方法计算得出的D占CFD计算得出的D的15.97%至18.82%，解析方法计算得出的D占解析方法计算得出的D的14.66%至16.21%。因此，尽管存在偏差，但解析方法为了解自身流体动力学特性提供了一种可行的方法。
