Electrostatic force calculation for an EWOD-actuated droplet

Baird, Eric; Young, Patrick; Mohseni, Kamran

doi:10.1007/s10404-006-0147-y

Cited by 61 publications

(49 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A better understanding of the physics of droplet actuation is derived from electrodynamics analysis, [23][24][25] which explains the phenomenon in terms of electrical forces generated on free charges in the droplet meniscus (in case of conductive liquids) or on dipoles inside of the droplet (in case of dielectric liquids). These forces can be calculated by integrating the Maxwell-Stress tensor, T ij (Eq.…”

Section: Physics Of Droplet Actuationmentioning

confidence: 99%

The Digital Revolution: A New Paradigm for Microfluidics

2009

View full text Add to dashboard Cite

The digital revolution has come to microfluidics. In digital microfluidics (DMF), discrete droplets are manipulated by applying electrical fields to an array of electrodes. In contrast to microchannels, in DMF each sample and reagent is individually addressable, which facilitates exquisite control over chemical reactions. Here, we review the state‐of‐the‐art in DMF, with a discussion of device formats, actuation physics, and biological and nonbiological applications. Along the way, we identify the key players in the field, and speculate on the advances and challenges that lie ahead. As with other fronts in the digital revolution, there have been and will be unexpected developments as DMF matures, but we posit that the future is bright for this promising technology.

show abstract

Section: Physics Of Droplet Actuationmentioning

confidence: 99%

The Digital Revolution: A New Paradigm for Microfluidics

2009

View full text Add to dashboard Cite

show abstract

“…3͒, we assume that the contact area with substrate is circular. 40 The electrostatic energy of the system is…”

Section: Theory Of Operationmentioning

confidence: 99%

Fast and reliable droplet transport on single-plate electrowetting on dielectrics using nonfloating switching method

2010

View full text Add to dashboard Cite

In a droplet transport based on electrowetting on dielectrics, the parallel-plate configuration is more popular than the single-plate one because the droplet transport becomes increasingly difficult without cover plate. In spite of the improved transport performance, the parallel-plate configuration often limits the access to the peripheral components, requesting the removal of the cover plate, the single-plate configuration. We investigated the fundamental features of droplet transport for the single-plate configuration. We compared the performance of several switching methods with respect to maximum speed of successive transport without failure and suggested nonfloating switching method which is inherently free from the charge-residue problem and exerts greater force on a droplet than conventional switching methods. A simple theory is provided to understand the different results for the switching methods.

show abstract

“…This section uses the electromechanical framework developed by Kumari et al [12] to highlight the physics underlying each of the three actuation regimes; similar considerations have been employed by Jones [44] and Chatterjee et al [45] to study frequency-dependent electrical actuation. The framework by Kumari et al [12] is used to develop a scaling analysis-based model to compare the actuation force in each of the three regimes.…”

Section: Electromechanical Modeling Of the Electrical Actuation Forcementioning

confidence: 99%

Electrical actuation-induced droplet transport on smooth and superhydrophobic surfaces

Bahadur¹,

Garimella

2010

International Journal of Micro-Nano Scale Transport

View full text Add to dashboard Cite

E El le ec ct tr ri ic ca al l a ac ct tu ua at ti io on n--i in nd du uc ce ed d d dr ro op pl le et t t tr ra an ns sp po or rt t o on n s sm mo oo ot th h a an nd AbstractElectrical control of liquid droplet motion and wettability has wide-ranging applications in the field of MEMS, lab-on-a-chip devices and surface engineering, in view of the resulting enhanced flow control opportunities, low power consumption and the absence of mechanical moving parts. This article summarizes recent progress towards understanding of the fundamentals underlying electrical actuation of droplets on smooth and superhydrophobic surfaces. Electrical actuation of liquid droplets with widely differing electrical properties on smooth surfaces is first discussed. Electromechanical considerations are employed to study the actuation force on a generic liquid droplet across the entire spectrum of electrical actuation regimes. The challenges in understanding the fluid flow and dissipation mechanisms associated with a discrete moving droplet are discussed. The role of electrical voltages, interfacial energies and surface morphology in determining droplet states (nonwetting Cassie state and wetting Wenzel state) and triggering state transitions on superhydrophobic surfaces is then mapped out. Critical phenomena associated with droplet transitions on superhydrophobic surfaces (energy barrier for the Cassie-Wenzel transition, lack of spontaneous reversibility of the Cassie-Wenzel transition, robustness of the Cassie state, and the role of the roughness elements) are analyzed. The article also highlights key avenues for future research in the fields of electrical actuation-based microfluidics and superhydrophobic surfaces. INTRODUCTIONElectrical actuation of liquid droplet motion on smooth and superhydrophobic surfaces has been studied as a tool for controlling microfluidic operations which determine the performance of lab-on-a-chip devices, optical systems, fluidic displays and other MEMS-based fluidic devices. Key advantages of electrical actuation of liquids (in the form of discrete droplets) over mechanical actuation include the absence of moving mechanical parts, opportunities for enhanced and reconfigurable flow control, compatibility with liquids of widely different electrical properties, compatibility with existing fabrication techniques, and ease of integration with a chip-based microfluidic platform. Electrical actuation techniques are also very energy-efficient, typically requiring only microwatts of power per microfluidic operation. Owing to these advantages, electrical actuation-based control has attracted significantly more research interest than competing non-mechanical liquid control technologies such as thermocapillarity [1] (reduction of surface tension by temperature, leading to fluid motion), optoelectrowetting [2] (light-controlled surface tension induced pumping) and vapor bubble-based pumping [3]. Electrical actuation of liquid droplets on smooth surfaces and its potential applications have been reviewed by Mugele and Ba...

show abstract

Electrostatic force calculation for an EWOD-actuated droplet

Cited by 61 publications

References 29 publications

The Digital Revolution: A New Paradigm for Microfluidics

The Digital Revolution: A New Paradigm for Microfluidics

Fast and reliable droplet transport on single-plate electrowetting on dielectrics using nonfloating switching method

Electrical actuation-induced droplet transport on smooth and superhydrophobic surfaces

Contact Info

Product

Resources

About