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A Very Stable High Throughput Taylor Cone-jet in Electrohydrodynamics.
M R Morad1, A Rajabi1, M Razavi1
1Sharif University of Technology, Department of aerospace engineering, Tehran, Iran.
Scientific Reports
|December 6, 2016
Summary
Researchers enhanced the stability of electric field-driven liquid jets using a hemispherical cap. This simple mechanism significantly broadens the operating range for Taylor cone-jet stability, enabling higher throughput for various applications.
Area of Science:
- Electrohydrodynamics
- Fluid Dynamics
- Applied Physics
Background:
- Stable capillary liquid jets driven by electric fields are crucial for applications like droplet formation, energy generation, and microfluidics.
- The Taylor cone-jet, a key phenomenon in electrohydrodynamics, exhibits limited stability concerning liquid flow rate (Q) and applied voltage (V).
Purpose of the Study:
- To introduce a simple mechanism for significantly extending the stability margin of the Taylor cone-jet.
- To achieve higher throughput in controlled liquid jet generation.
Main Methods:
- Investigated the stability of ethanol cone-jets emitted from a simple nozzle.
- Implemented a hemispherical cap installed above the nozzle to modify the electric field distribution.
- Determined the stability margins for ethanol, methanol, 1-propanol, and 1-butanol across varying flow rates and voltages.
- Analyzed the effect of a gravity-directed nozzle on cone-jet stability.
Main Results:
- A simple nozzle produced a stable cone-jet within 1 kV, with stability decreasing to 2 ml/h flow rate.
- Installing a hemispherical cap extended the stability margin to 5 kV at low flow rates, extending to 65 ml/h.
- The hemispherical cap significantly increased the operational range and throughput of the Taylor cone-jet.
- Gravity-directed nozzles demonstrated enhanced stability and consistent spray direction.
Conclusions:
- A hemispherical cap is an effective and simple method to greatly enhance Taylor cone-jet stability margins.
- This enhancement allows for higher throughput, broadening the applicability of electric field-driven liquid jets.
- The findings are applicable to various alcohols and suggest potential for improved control in electrohydrodynamic applications.
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