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Updated: Oct 1, 2025

Glass-Based Devices to Generate Drops and Emulsions
Published on: April 5, 2022
Contactless Method of Emulsion Formation Using Corona Discharge
Amir Dehghanghadikolaei1, Mohcen Shahbaznezhad2, Bilal Abdul Halim1
1Department of Mechanical, Industrial, and Manufacturing, The University of Toledo, Toledo, Ohio 43615, United States.
This study introduces a novel contactless method for creating water-in-oil emulsions using electrohydrodynamics (EHD). The technique simultaneously forms and collects emulsions via corona discharge, offering a low-cost, continuous process.
Area of Science:
- Fluid Dynamics
- Colloid Science
- Electrokinetics
Background:
- Electroemulsification utilizes electrohydrodynamic (EHD) forces for droplet manipulation.
- Existing methods often require direct contact, limiting scalability and continuous operation.
Purpose of the Study:
- To develop a contactless, top-down method for simultaneous emulsion formation and collection.
- To investigate the formation of water-in-oil (W/O) emulsions using corona discharge and EHD pumping.
Main Methods:
- A contactless corona discharge generated by a sharp electrode ionizes water vapor.
- Ionic wind (electroconvection) drags ionized droplets into an oil medium.
- A modulated bottom electrode induces an EHD pumping effect for oil medium motion.
Main Results:
- Continuous formation of W/O emulsions was achieved through contactless corona discharge and EHD pumping.
- The study analyzed the influence of corona discharge voltage, electrode distances, and oil depth on emulsion droplet size.
- A low-cost, scalable process for W/O emulsion generation was demonstrated.
Conclusions:
- The presented top-down method offers a novel, contactless approach to W/O emulsion formation.
- This technique integrates emulsion generation with pumping and collection, simplifying the process.
- The findings highlight the potential for efficient and continuous emulsion production using EHD principles.
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