Particle image velocimetry is applied in this study to measure the wake flow field of a Panamax Bulker ship model under the ballast condition. This investigation revealed that the Froude number is 0.167. The time-averaged velocity, turbulent fluctuations, turbulent kinetic energy (TKE), Reynolds stresses, and vorticity information were measured to perform a comparison with the design condition. The time-averaged velocity contours indicated that the ballast and design conditions have distinct hook-like axial velocity contours; however, they appeared at different positions. The big difference under the ballast condition is that the top of the propeller disk area is near the free surface and a region with strong root mean square velocity fluctuation is formed near the free surface. The TKE, the Reynolds stresses, and the hub cap vortex (Hcv) are all affected by the turbulent velocity fluctuation region under the ballast condition. A strong bilge vortex (Bv) is produced when the water flows through the U-shaped stern for the design and ballast conditions.

中文翻译：

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压载状态下巴拿马型散货船模型后的尾流场的立体粒子图像测速测量

在这项研究中，应用了粒子图像测速技术来测量压载状态下巴拿马型散货船模型的尾流场。这项调查显示，弗洛德数为0.167。测量时间平均速度，湍流涨落，湍动能（TKE），雷诺应力和涡度信息，以与设计条件进行比较。时间平均速度轮廓线表明，压载物和设计条件具有明显的钩状轴向速度轮廓线；但是，它们出现在不同的位置。压载条件下的最大区别在于，螺旋桨盘区域的顶部靠近自由表面，并且在自由表面附近形成了均方根速度波动较大的区域。雷诺兹强调，TKE 在压载条件下，轮毂盖涡（Hcv）均受湍流速度波动区域的影响。在设计和压载条件下，水流过U型船尾时会产生强烈的舱底涡（Bv）。