微尺度空泡溃灭驱使微球运动的机理研究
发布时间：2018-08-26 16:02
【摘要】：受限空泡的溃灭是气泡动力学的核心问题,研究表明毫米尺度的空泡溃灭可以拉动附近同尺度的悬浮颗粒运动.本文针对受限空泡溃灭在微尺度下的行为开展研究,通过气泡驱动的球形微马达实验,给出了微气泡溃灭形成射流从而显著推动马达前进的现象,但由于溃灭时间很短,Micro PIV系统不能给出足够的流动细节.进而采用基于流体体积的数值手段模拟了这一过程,获得了流场的时空分布,并通过积分估算了微球获得的冲量,给出了微球所能达到的速度.结果表明这一问题与尺度密切相关,微尺度下空泡溃灭足以推动微球显著运动,在气泡尺寸固定的情况下,微球半径越小,微球与气泡间距离越近,推动的效果越明显.冲量定理则定性地解释了宏观尺度与微尺度下存在差异的原因.这一特殊的微流动问题不但扩展了空化研究的尺度范围,揭示了微尺度下空泡与颗粒作用的特性,而且对提高微马达的驱动效率也具有重要意义.
[Abstract]:The collapse of confined cavitation is the core problem of bubble dynamics. It is shown that the bubble collapsing in millimeter scale can pull the motion of suspended particles of the same size nearby. In this paper, the behavior of confined cavitation collapsing at microscale is studied. Through the experiment of spherical micromotor driven by bubble, the phenomenon that the micro bubble collapses to form a jet, thus propelling the motor forward significantly, is given. However, due to the short collapse time, micro PIV system can not give enough flow details. Then the numerical method based on the volume of fluid is used to simulate the process, and the space-time distribution of the flow field is obtained. The impulse obtained by the microsphere is estimated by integral, and the velocity that the microsphere can achieve is given. The results show that this problem is closely related to the scale. The bubble collapse in the microscale is enough to promote the significant movement of the microspheres. When the bubble size is fixed, the smaller the radius of the microsphere, the closer the distance between the microsphere and the bubble, and the more obvious the promotion effect is. The impulse theorem qualitatively explains the difference between macro scale and micro scale. This special micro-flow problem not only expands the scale range of cavitation research, but also reveals the characteristics of cavitation and particle interaction in micro-scale, and also plays an important role in improving the driving efficiency of micro-motor.
【作者单位】： 西安建筑科技大学环境与市政工程学院;
【基金】：国家自然科学基金应急管理项目(批准号:11447133);国家自然科学基金青年基金(批准号:11602187) 陕西省自然科学基础研究计划青年人才项目(批准号:2016JQ1008) 陕西省教育厅专项科研计划(批准号:15JK1385) 西部绿色建筑国家重点实验室培育基地自主科研项目资助的课题~~
【分类号】：O35
本文编号：2205419
[Abstract]:The collapse of confined cavitation is the core problem of bubble dynamics. It is shown that the bubble collapsing in millimeter scale can pull the motion of suspended particles of the same size nearby. In this paper, the behavior of confined cavitation collapsing at microscale is studied. Through the experiment of spherical micromotor driven by bubble, the phenomenon that the micro bubble collapses to form a jet, thus propelling the motor forward significantly, is given. However, due to the short collapse time, micro PIV system can not give enough flow details. Then the numerical method based on the volume of fluid is used to simulate the process, and the space-time distribution of the flow field is obtained. The impulse obtained by the microsphere is estimated by integral, and the velocity that the microsphere can achieve is given. The results show that this problem is closely related to the scale. The bubble collapse in the microscale is enough to promote the significant movement of the microspheres. When the bubble size is fixed, the smaller the radius of the microsphere, the closer the distance between the microsphere and the bubble, and the more obvious the promotion effect is. The impulse theorem qualitatively explains the difference between macro scale and micro scale. This special micro-flow problem not only expands the scale range of cavitation research, but also reveals the characteristics of cavitation and particle interaction in micro-scale, and also plays an important role in improving the driving efficiency of micro-motor.
【作者单位】： 西安建筑科技大学环境与市政工程学院;
【基金】：国家自然科学基金应急管理项目(批准号:11447133);国家自然科学基金青年基金(批准号:11602187) 陕西省自然科学基础研究计划青年人才项目(批准号:2016JQ1008) 陕西省教育厅专项科研计划(批准号:15JK1385) 西部绿色建筑国家重点实验室培育基地自主科研项目资助的课题~~
【分类号】：O35
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1 黄景泉;空泡溃灭时的流场[J];应用数学和力学;1989年03期
2 陆力,许协庆;固液两相流体中刚性平面边壁附近的空泡溃灭计算[J];水动力学研究与进展(A辑);1990年04期
3 陆力,黄继汤,许协庆;固液两相流体中的空泡溃灭计算[J];力学学报;1991年01期
4 李贝贝;张宏超;倪晓武;陆建;;不同环境压强下激光空泡溃灭射流的实验研究[J];激光技术;2012年06期
5 何国庚,罗军,黄素逸;空泡溃灭的Bjerknes效应[J];水动力学研究与进展(A辑);2000年03期
6 倪汉根，何子干;空泡溃灭冲击波对流场携带颗粒的作用[J];大连理工大学学报;1994年06期
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