The spatiotemporal structure of the flow field during particle–cloud sedimentation has not been sufficiently investigated. In this study, experiments on the sedimentation process of particle clouds in water are conducted using hydrogel particles with a refractive index similar to that of water as the settling particles. The flow field during the sedimentation process of particle clouds in water is measured using particle image velocimetry (PIV). Although the measurement conditions in this study are restricted to one condition owing to the limitations of the measurable area by our PIV system and the available hydrogel particles, the measurement target is novel because it has not been measured so far. The spatiotemporal structure of the turbulent flows is investigated by analyzing the turbulent flows induced by the sedimentation particles using the PIV system. Furthermore, the turbulent structure of the vortex formed by particle sedimentation is examined.

中文翻译：

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使用 RIM-PIV 研究颗粒沉降引起的湍流

颗粒云沉积过程中流场的时空结构尚未得到充分研究。本研究以折射率与水相似的水凝胶颗粒作为沉降颗粒，进行了水中颗粒云的沉降过程实验。使用粒子图像测速（PIV）测量水中粒子云沉降过程中的流场。尽管由于我们的PIV系统的可测量区域和可用的水凝胶颗粒的限制，本研究中的测量条件仅限于一种条件，但测量目标是新颖的，因为迄今为止尚未测量过。通过使用 PIV 系统分析沉降颗粒引起的湍流，研究了湍流的时空结构。此外，还检查了颗粒沉降形成的涡流的湍流结构。