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Electric field and viscous fluid polarity effects on capillary-driven flow dynamics between parallel plates
Rizwan Ul Hassan1, Shaheer Mohiuddin Khalil2, Saeed Ahmed Khan2,3
1Department of Mechanical Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.
Heliyon
|May 30, 2023
Summary
Electric fields significantly enhance the flow of viscous fluids in microfluidic systems, improving underfill application performance by up to 45%. This research offers a new method for controlling fluid dynamics in micro-electro-mechanical systems.
Area of Science:
- Microfluidics and micro-electro-mechanical systems (MEMS).
- Biomedical engineering and fluid dynamics.
Background:
- Capillary-driven flow of viscous fluids in microfluidic devices, such as underfill applications, is often sluggish.
- Improving this flow is crucial for the commercialization of MEMS devices.
Purpose of the Study:
- To investigate the impact of electric potential on the capillary-driven flow of viscous fluids.
- To explore methods for enhancing underfill flow in microfluidic applications.
Main Methods:
- Experimental investigation of viscous fluid flow under varying electric potentials (up to 500 V).
- Alteration of fluid polarity using NaCl additives to study conductive fluid behavior.
- Time-dependent numerical simulations using COMSOL Multiphysics, incorporating quasi-electrostatic, level set, and laminar two-phase flow modules.
Main Results:
- Increasing electric potential to 500 V enhanced underfill flow length by 45% for viscous fluids.
- Highly viscous conductive fluids (glycerol with 0.5-4% NaCl) showed a 20-41% increase in flow length at 500 V compared to 0 V.
- Numerical simulation results closely matched experimental data, with an average deviation of 4-7%.
Conclusions:
- Electric fields can effectively control and enhance the capillary-driven flow of highly viscous fluids.
- The observed enhancement is attributed to induced polarity and increased fluid permittivity under electric potential.
- This approach holds significant potential for optimizing underfill applications in MEMS devices.
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