Electrospraying

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Electrospraying Electospinning
Nils André REINKE, Universitat Duisburg,
BRD Seminar Self-organized and artificial
nanostructures, applied physics, summer-term
2002.
Overview I. Various kinds of spraying II. Outflow
of a liquid from a capillary III. Rayleigh
instability IV. The future development and
application
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I. Various kinds of spraying
Bernoulli effect
sprayer
Liquid suction
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Spraying caused by a spinning disc
Drop-mode
V ...circumferential velocity
Centrifugal acceleration
Ligament-mode
Sheet-mode
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Ultrasound spraying
Ultrasound builder
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Electrospraying

Charged droplets
Nano proportions
Nanoparticles nanofibres
Charged particles interact with external el.stat.
Field, their flow can be driven by the
field. Applications DeskJet printers,
lacquering, painting, Fuel- charger - power -
cell for car engines.
-
More expensive
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II. Outflow of a liquid from a capillary
Without an external field
Influences by the external el stat. Field
Equal flows
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Rayleigh instability caused by a droplet charge
Split force
Gauss theorem
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Rayleigh instability caused by charged jet
L
nanofibre
Length charge density