Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, India.
Electrophoresis. 2019 Nov;40(22):2971-2978. doi: 10.1002/elps.201900272. Epub 2019 Aug 23.
We explore a simple strategy of generating strong rotating flow in a stationary surface-droplet, using an intricate interplay of local electrical and thermal fields. Wire electrodes are employed to generate on-spot heating without necessitating any elaborate micro-fabrication, which causes strong local gradients in electrical properties to induce mobile charges into the droplet. Applying a low voltage (∼10 V), strong rotational velocity of the order of mm/s can be achieved in the system, within the standard operating ranges of operating and geometrical parameters. Further, altering the diameter of the electrode, vortices can be tuned locally or globally in low power budget, without incurring any droplet oscillations. These results may turn out to be of immense consequence in enhancing micromixing in a plethora of droplet based applications ranging from thermal management to medical diagnostics to be potentially employed in resource-limited settings.
我们探索了一种在静止液滴中产生强旋转流的简单策略，该策略利用局部电场和热场的复杂相互作用。使用金属丝电极进行现场加热，而无需任何复杂的微加工，这会导致电性能的强烈局部梯度，从而将可移动电荷引入液滴中。在标准的操作参数范围内，施加低电压（约 10 V）时，系统中可以实现毫米/秒量级的强旋转速度。此外，通过改变电极的直径，可以在低功率预算下局部或全局地调节涡流，而不会引起液滴的任何振荡。这些结果可能在增强基于液滴的应用中的微混合方面具有重要意义，这些应用从热管理到医疗诊断，可能在资源有限的环境中得到应用。
