Transient interaction between a particle and an attached bubble with an application to cavitation in silt-laden flow
Transient interaction between a particle and an attached bubble with an application to cavitation in silt-laden flow
复制标题
颗粒与附着气泡之间的瞬态相互作用及其在含泥流空化中的应用
DOI：
10.1063/1.5044237
复制
发表时间：
2018-08-01
影响因子：
4.6
通讯作者：
Han, Rui
中科院分区：
文献类型：
--
作者：
Li, Shuai;Zhang, A-Man;Han, Rui
这项研究旨在阐明悬浮粒子与附着的气泡之间的复杂相互作用，这与粉砂流中的空化有关。使用高速摄影进行系统的实验，其中的气泡是通过水下电气排放量产生的。发现气泡粒子相互作用很大程度上取决于两个无量纲参数，即，粒子 - 泡沫尺寸比率lambda（l）和粒子 - 液密度比率lambda（RHO）。当Lambda（Rho）等于2.61时，普遍观察到气泡分裂现象，并且随着Lambda（L）的降低，粒子射击效果（气泡膨胀过程和气泡粒子脱离之后的粒子加速度）变得更加明显。如果lambda（l）<与0.34相似，则粒子速度保持正（远离气泡），否则在气泡塌陷阶段，粒子速度降至零（朝向气泡）以下。随着Lambda（Rho）的增加，粒子的速度较低，但冲动较高，并且气泡颈部现象更为明显。我们的边界积分模拟很好地重现了实验，包括粒子动力学，包裹粒子的气泡，气泡颈和脱离以及蘑菇形气泡。气泡粒子脱离后，向内绘制了脱离位置周围的液体并在对称轴上碰撞，从而导致气泡和粒子之间的局部高压区域形成，即使在气泡塌陷相中，也会第二次加速粒子。由AIP出版出版。
This study aims to elucidate the complex interaction between a suspended particle and an attached bubble, which is associated with cavitation in silt-laden flow. Systematic experiments are performed with high-speed photography, in which bubbles are generated by underwater electric discharge means. The bubble-particle interactions are found to be strongly dependent on two dimensionless parameters, i.e., the particle-bubble size ratio λL and the particle-liquid density ratio λρ. When λρ equals 2.61, the bubble split phenomenon is universally observed and the particle shooting effect (the particle acceleration during bubble expansion and after bubble-particle detachment) becomes more obvious as λL decreases. If λL < ∼0.34, the particle velocity keeps positive (away from the bubble), otherwise the particle velocity drops below zero (toward the bubble) during the bubble collapse phase. As λρ increases, the particle achieves a lower velocity but a higher impulse, and the bubble necking phenomenon is more pronounced. Our boundary integral simulations reproduce the experiments extremely well, including the particle dynamics, the bubble wrapping the particle, the bubble necking and detachment, and the mushroom-shaped bubble. After the bubble-particle detachment, the liquid around the detachment location is drawn inward and collides on the axis of symmetry, leading to the formation of a localized high pressure region between the bubble and the particle, which accelerates the particle for the second time even in the bubble collapse phase.This study aims to elucidate the complex interaction between a suspended particle and an attached bubble, which is associated with cavitation in silt-laden flow. Systematic experiments are performed with high-speed photography, in which bubbles are generated by underwater electric discharge means. The bubble-particle interactions are found to be strongly dependent on two dimensionless parameters, i.e., the particle-bubble size ratio λL and the particle-liquid density ratio λρ. When λρ equals 2.61, the bubble split phenomenon is universally observed and the particle shooting effect (the particle acceleration during bubble expansion and after bubble-particle detachment) becomes more obvious as λL decreases. If λL < ∼0.34, the particle velocity keeps positive (away from the bubble), otherwise the particle velocity drops below zero (toward the bubble) during the bubble collapse phase. As λρ increases, the particle achieves a lower velocity but a higher impulse, and the bubble necking phenomenon is more pronou...