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Jens Eggers How to make small things
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Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

Dec 26, 2015

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Page 1: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

Jens Eggers

How to make small things

Page 2: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

Singularities!

experiment by Shi et al.

very small

scales created

here

Page 3: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

•Singularities are nature’s way of making small things

Why singularities?

•The simple mathematical structure of singularitiespermits detailed control

Page 4: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

Printing challenges

O. Basaran problem:satellites

satellite “engineer’sdream”

Page 5: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

experiment byD.H. Peregine et al.,JFM `90 computed

from 1-dmodel

simulation from J. Eggers and T.F. Dupont,JFM 94

Water drop

Page 6: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

experiment bySpudich et al.

Two-fluid breakup: Cell division

Cohen, Brenner,Eggers, Nagel, PRL’99

Page 7: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

experiment byCh. Wagner

1-D simulation

Polymeric fluid (100 ppm of PEO)

Page 8: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

Moseler and Landman, Science 2000

Nanojet

symmetric pinching!J. Eggers, PRL `02

Page 9: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

sphere sphere

Coalescence

motion driven by surfacediffusion

small enclosure

Page 10: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

A sharp cusp

Lorenceau et al, PRL ‘03

V fluid,

air,

fl

g

200 m

Ca

Page 11: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

viscous fluid

fluid jet

cusp forms

Pouring a viscous liquid

E. Lorenceau,D. Quéré,J. Eggers, PRL ‘04

cusp

J. Eggers, PRL ‘01

E. Lorenceau,D. Quéré,PRL ‘03

Page 12: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

Quest for microdrops: flow

Cohen et al., Science `01: selective withdrawal

but: smallest tip size 200 m

Page 13: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

Small scales: bubble tip

Increase flow rate

tip radius(microns)

flow rate (g/s)

bubble

drain0.5mm

experiment byS. Courrech du Pont

Page 14: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

experiment byPantano et al.

New structure: electric jetsTaylor cone

jettiny droplets

Page 15: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

Moving contact lines

experiment by Podgorski et al., PRL `01

orientation of inclined plane

advancing contact line

receding contact line

Page 16: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

Contact line deposits

Robert Deegan,

PRE `00

evaporationdeposit pinning-unpinning-

pinning…

0.1 particlesm surfactant

Page 17: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

STM tips

Quaade + Oddershede EPL `02

log(tipsize)

log(tc-t)

makes nano-sized

tips!

Page 18: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

•Singularities occur in a great variety of systems

Conclusions

•Self-similarity is the natural language to describe singularities.

•Challenge: what ways are there to fixate singularities?

Page 19: Jens Eggers How to make small things. Singularities! experiment by Shi et al. very small scales created here.

( , )h z t

2 20( v ) 0zh ht mass conservation

20

0 0 0 2

( v )v v v 3

hz z

z z

hpt

inertia surf. tens. viscosity

J. Eggers, T. F. Dupont, JFM `94

2

32 2

1

1 ( ) 1 ( )

z

z z

hp

h h h

Laplace Pressure

One-dimensional approximation