To investigate the bubble sweep-down phenomenon of a scientific research ship from the perspective of its flow mechanism, the flow-field characteristics of the bow were measured in a towing-tank environment. First, the silk-thread method was used to visualise the streamline characteristics of the bow. Next, the flow field of the bow was measured using multiple two-section 2-dimensional computed tomography scans with stereoscopic particle image velocimetry. The flow-field information of different sections at different speeds (e.g., velocity distribution, vector characteristics, and streamline distribution) were then obtained. A 3-dimensional (3D) three-component (3C) space reconstruction of the time-averaged flow field in the bow was thus realised. From the visualisation results, the flow field in the bow generally exhibits a downward movement trend. The flow structure of the bow flow field was found to be closely related to the wave-making change of the bow. On the other hand, the cross-sectional flow characteristics and 3D reconstruction results showed that with the bubble sweep-down, some bubbles flowed along the bilge and amassed with other bubbles, breaking through the geometric inflection point of the bilge. Compressed by the bilge vortex, they slid backward and affected the operation of acoustic equipment.

为了从流动机理的角度研究某科研船的气泡扫掠现象，在拖曳水舱环境中测量了船首的流场特性。首先，采用丝线法将弓的流线特征可视化。接下来，使用具有立体粒子图像测速法的多个二维二维计算机断层扫描扫描测量船首的流场。然后获得不同速度下不同截面的流场信息（例如，速度分布、矢量特征和流线分布）。因此实现了船首中时间平均流场的 3 维 (3D) 三分量 (3C) 空间重建。从可视化结果来看，船首流场一般呈下降趋势。发现船首流场的流动结构与船首的造浪变化密切相关。另一方面，横截面流动特征和3D重建结果表明，随着气泡的下沉，一些气泡沿着舱底流动并与其他气泡聚集在一起，突破了舱底的几何拐点。在舱底涡流的压缩下，它们向后滑动，影响了声学设备的运行。突破舱底的几何拐点。在舱底涡流的压缩下，它们向后滑动，影响了声学设备的运行。突破舱底的几何拐点。在舱底涡流的压缩下，它们向后滑动，影响了声学设备的运行。