Quinto-Su Pedro A, Lim Kang Y, Ohl Claus-Dieter
Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore.
Phys Rev E Stat Nonlin Soft Matter Phys. 2009 Oct;80(4 Pt 2):047301. doi: 10.1103/PhysRevE.80.047301. Epub 2009 Oct 6.
We study experimentally the dynamics of laser-induced cavitation bubbles created inside a narrow gap. The gap height, h , is varied from 15 to 400 microm and the resulting bubble dynamics is compared to a semiunbounded fluid. The cavitation bubbles are created with pulsed laser light at constant laser energy and are imaged with a high-speed camera. The bubble lifetime increases with decreasing gap height by up to 50% whereas the maximum projected bubble radius remains constant. Comparing the radial dynamics to potential flow models, we find that with smaller gaps, the bubble-induced flow becomes essentially planar, thus slower flows with reduced shear. These findings might have important consequences for microfluidic applications where it is desirable to tune the strength and range of the interactions such as in the case of cell lysis and cell membrane poration.
我们通过实验研究了在狭窄间隙内产生的激光诱导空化泡的动力学特性。间隙高度h在15至400微米之间变化，并将由此产生的泡动力学特性与半无限流体进行了比较。空化泡由脉冲激光在恒定激光能量下产生，并用高速相机成像。泡寿命随着间隙高度的减小而增加，增幅高达50%，而泡的最大投影半径保持不变。将径向动力学特性与势流模型进行比较，我们发现，间隙越小，泡诱导的流动基本上变得平面化，从而流动速度变慢，剪切力减小。这些发现可能对微流体应用具有重要意义，在微流体应用中，如细胞裂解和细胞膜穿孔的情况下，需要调节相互作用的强度和范围。
