Behaviors of a prolate ellipsoid inside circular tube Poiseuille flow are studied experimentally. In the study, Reynolds number Re ∈ (100,700) and the confinement ratio D/A ∈ (1.2,2.8) are considered, where D is the diameter of the tube and A is the length of the major axis of the ellipsoid. Two typical stable motion modes are identified, namely, the horizontal, and inclined modes. Then another inclined mode (inclined mode II) is found at high Reynolds number (Re ∈ (1000,3200)) and small D/A, and the inclined angle of ellipsoid increases with the increase of Re. The possible mechanism is explained. Our experiment shows that the lagging velocity U increases as Re increases. Further numerical analysis using FLUENT shows that due to the increase of U, the moment acting on the particle would make the inclined angle of the particle increase.

中文翻译：

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管泊泊流中椭圆形颗粒的实验研究

实验研究了圆管泊泊流中椭圆形椭球的行为。在研究中，雷诺数重新∈（100700）和约束比d /甲∈（1.2,2.8）被认为是，其中d是管的直径和阿是椭圆的长轴的长度。确定了两种典型的稳定运动模式，即水平和倾斜模式。然后另一个倾斜模式（倾斜模式II）是在高雷诺数发现（再∈（1000,3200））和小d / A，和的椭球的增加与增加的倾斜角度重新。说明了可能的机制。我们的实验表明，滞后速度U随着Re的增加而增加。使用FLUENT进行的进一步数值分析表明，由于U的增加，作用在粒子上的力矩会使粒子的倾斜角增加。