Dynamic response of a thin sessile drop of conductive liquid to an abruptly applied or removed electric field

We discover novel types of stationary cone-jet steams emitting from a nozzle of a syringe loaded with a conductive liquid. The predicted cone-jet-flow geometries are based on the analysis of the electrohydrodynamic equations including the surface current. The electric field and the flow velocity field inside the cone are calculated. It is shown that the electric current along the conical stream depends on the cone angle. The stable values of this angle are obtained based on the Onsager’s principle of maximum entropy production. The characteristics of the jet that emits from the conical tip are also studied. The obtained results are relevant both for the electrospraying and electrospinning processes.

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Dynamic Response of an Electrospun PVDF-Fe3O4 Piezoelectric Composite Microfiber

ASME 2019 Conference on Smart Materials, Adaptive Structures and Intelligent Systems ◽

10.1115/smasis2019-5686 ◽

2019 ◽

Author(s):

Krishna Chytanya Chinnam ◽

Arnaldo Casalotti ◽

Giulia Lanzara

Keyword(s):

Electric Field ◽

Dynamic Response ◽

Resonance Frequency ◽

Piezoelectric Composite ◽

Test Results ◽

Ac Electric Field ◽

Wide Range ◽

Pvdf Matrix ◽

Fine Tune

Abstract In this paper the dynamic response of an electrospun nanocomposite piezoelectric microfiber is investigated. The microfiber is formed by magnetic nanoparticles dispersed in Polyvinylidene (PVDF) matrix. Focus is given on the influence of an AC electric field on the dynamic response of the microfiber. In particular, the resonance frequency of the fiber was assessed under an increasing AC electric field at a wide range of frequencies. The electromechanical test results show that the resonance frequency of the fiber is influenced by the applied voltage and, for this case study, it decreases with increasing voltage. The results reported in this paper suggest that, once the mechanism behind such response is fully understood, composite piezoelectric microfibers can be used to fine-tune the resonance frequency of hosting devices.

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Hydrodynamic characteristics of weakly conductive liquid media in the non-uniform electric field

Mathematica Montisnigri ◽

10.20948/mathmontis-2019-45-6 ◽

2019 ◽

Vol 45 ◽

pp. 74-84

Author(s):

M.S. Apfelbaum ◽

◽

A.N. Doludenko ◽

Keyword(s):

Electric Field ◽

Uniform Electric Field ◽

Hydrodynamic Characteristics ◽

Liquid Media ◽

Conductive Liquid

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DYNAMIC RESPONSE OF CARBON NANOTUBES DISPERSED IN NEMATIC LIQUID CRYSTAL

NANO ◽

10.1142/s1793292007000350 ◽

2007 ◽

Vol 02 (01) ◽

pp. 41-49 ◽

Cited By ~ 48

Author(s):

SANG YOUN JEON ◽

KYUNG AH PARK ◽

IN-SU BAIK ◽

SEOK JIN JEONG ◽

SEOK HO JEONG ◽

...

Keyword(s):

Carbon Nanotubes ◽

Liquid Crystal ◽

Electric Field ◽

Dynamic Response ◽

Nematic Liquid Crystal ◽

Density Functional ◽

Strong Electric Field ◽

Optical Microscope ◽

Analysis Of Dynamics ◽

Vertical Cell

The alignment and dynamic response of carbon nanotubes (CNTs) in nematic liquid crystal (NLC) medium induced by strong electric field have been observed through polarizing optical microscope. Density-functional calculations suggest that LC molecule anchors helically to the CNT wall to enhance π-stacking with a binding energy of nearly -2.0 eV due to a considerable amount of charge transfer from LC molecule to CNT, resulting in the formation of excess charges and permanent dipole moment in CNTs. Under strong electric field, the motion of CNTs distorted the director of adjacent LC molecules. Our detailed analysis of dynamics revealed that the four-lobe textures in vertical cell and two vertical stripes in in-plane switching cell were strongly correlated, i.e., the side view of textures by the vertical motion of CNTs in vertical cell was similar to the textures in in-plane switching cell. Interestingly, the magnitude of textures in microscope was strongly dependent on the size of CNTs and the applied field strength. The statistical size distribution of textures similar to that of CNTs provided information for the degree of dispersion of CNTs.

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