Elongational Index

(1)

Ch 01

Introduction to complex fluids

(2)

Solid --- Liquid

Ideal Solid --- Most Materials --- Ideal Fluid

Elastic --- Viscoelastic --- Viscous

Strain

0 time

Stress

0 time

Stress

0 time Stress

0 time

(3)

Solid Like --- Liquid Like

Ideal Solid --- Most Materials --- Ideal Fluid

Purely Elastic --- Viscoelastic --- Purely Viscous

γ

τ = G τ = η γ _&

( )

^T

( ( )

^T

)

p

We u

p

u

p p

u u u

t

τ + ^⎛ ⎜ ⎝ ^∂ ∂ τ + ⋅∇ − ∇ τ ⋅ − ⋅∇ τ τ ^⎞ ⎟ ⎠ = β ∇ + ∇

( )

2 , , , ,

Re (1 )

0 p p

p

f

u u u p u

t u

τ λ β η

β τ

τ

=

⎛ ∂ + ⋅∇ ⎞ = −∇ + ∇ ⋅ + − ∇

⎜ ∂ ⎟

⎝ ⎠

∇ ⋅ =

u

(4)

Time-dependent Viscoelastic Behavior

•

Old Testament Prophetess who said :

"The Mountains Flowed before the Lord"

•

Everything Flows if you wait long enough!

•

Deborah Number, De - The ratio of a characteristic time of a material (τ) to a characteristic time of the process (Τ)

De = τ/Τ

(5)

(6)

Rheology

• The science of flow and deformation of matter (complex fluids)

• Viscoelastic

• Deborah number

• Processing technology

De = τ/Τ

Mathematical rheology Mathematical theology

(7)

ABS

(8)

ABS (Acrylonitrile-Butadiene-Styrene)

Particle

size Gel

content Graft

ratio Impact

strength Hard-

ness Tensile

strength Flexural

strength VST gloss

ABS-4 3075 86 42 26.7 96.4 402 582 93.7 103.9

ABS-5 3100 82 69 24.1 95.3 393 567 95.1 101.7

(9)

G’ and η* of ABS

0.01 0.10 1.00 10.00 100.00 1000.00

FREQUENCY

100 1000 10000 100000

G',VISCOSITY

ABS-4 ABS-5

(10)

G’ vs. graft ratio

20 40 60 80 100 120

Graft ratio 10

100 1000 10000 100000

G' at w=0.1

(11)

Sheet grade 礱獺

(沁茿梞汬籤艃 ABS)

• 沁茿梞汬籤艃: 梞礩枾枾觩, 溶獺梳槆

• Sheet 迧瘡礱獺 (gel)

• 1鈔 test腬 resin 脙 3贱累舯

• Test 繽盤莶腢苖汐脭籓梳槆繽盤莶矇粀- Claim

• 綺蕗枾胱褮槬汬腬粿衇甇濍腐矇粀郡湊盤莶琌褦莯

• 盤莶艪茒礭糀

• 轕枾矓砿針碞

• 盤莶都桮矓砿瞺莞獦???

(12)

Competition with HIPS

• 沁茿梞汬籤艃 ABS,HIPS 矃礭

• ABS湊舓梾艊綺, HIPS湊枾桧桻荛珕

• 躜枾: ABS 1500$/MT, HIPS 800$/MT

• 瀅檓: ABS 3.5t, HIPS 4-5t

• 枾桧桻荛纍釜

• ABS 籏艃腡衇湊 HIPS琌莞釠郡梞茪郱

• Sheet 瀅檓 down

• 蕛梳糔醝糔鄭籤

• 莫榹矓砿瞺莞獦???

(13)

Kingdom of rheology

14 ^th ICR, Aug.22-27, Seoul

• Computational rheology

• Flow instability

• Foams, emulsions & surfactants

• Foods & biomaterials

• Materials processing

• Microstructural modeling

• Nanorheology & microfluidics

• Non-Newtonian fluid mechanics

• Polymer melts

• Polymer solutions

• Rheometry & experimental methods

• Solids & composites

• Suspensions & colloids

(14)

Challenges

• Biorheology

– Hemorheology, microfluidics

• IT rheology

– ACF rheology, coating

• Nanorheology

– Clay, CNT

• Modeling and simulation

(15)

Biorheology

Cause of death(USA)

American Heart Association 2003 Cardiovascular

Disease 49.9%

Cancer 32.4%

Accidents 7.1%

Etc. 10.4%

Extra-corporeal life supporter

RBC deformation and hemolysis

(16)

Diabetes Association

• Most diabetics have hyperviscosity by one or other mechanism.

(Dintenfass L, 1989)

• The Complication of diabetics

( Diabetic Retinopathy, Nephropathy, Nervous Diease )

Heathy retinal capillaries Heathy retinal capillaries

Diabetic retinal capillaries Diabetic retinal capillaries

Diabetic Retinopathy

(17)

Introduction – RBC

In pure

shear flow

(18)

Result

EI = 0.024979 EI = 0.03977 EI = 0.2453 EI = 0.348132

aspect ratio = 1.05 major axis = 107.9

minor axis =102.7

aspect ratio = 1.12 major axis = 97.9 minor axis = 87.7

aspect ratio = 1.65 major axis = 120.8

minor axis = 73.2

aspect ratio = 2.0681073 major axis = 134.48761 minor axis = 65.029320

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45

0 200 400 600 800 1000 1200

Shear rate

Elongational Index

EI = 0.392697 EI = 0.414989

aspect ratio = 2.29 major axis = 140.1 minor axis = 61.1

aspect ratio = 2.42

major axis = 145.2

minor axis = 60.0

(19)

BLOOD VISCOSITY

plasma viscosity plasma

viscosity erythrocyte

deformability erythrocyte

deformability leukocytes hematocrit

erythrocyte aggregation erythrocyte aggregation

Early diagnosis of heart disease

(20)

Normal & Patients

ASI

20 30 40 50 60 70 80 90

Avg EI 0.3

0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40

Normal Patient

ASI

20 40 60 80 100 120

Avg EI 30

0.38 0.40 0.42 0.44 0.46 0.48 0.50 0.52 0.54

Normal Patient

Shear rate= 0.3 Shear rate= 30

(21)

stress (Pa)

0.1 1 10 100 1000

EI

0.0 0.2 0.4 0.6

0.8 pure shear flow - newly tested

centerline of 4:1 contraction

(22)

Glass size vs. Coating Method

IT rheology

Spin

Slit/Spin

Slit

(23)

D layer (B)

D layer (top) P layer

T electode B electrode Seal

Glass In

Washing

Coat Dry

Washing MgO Depo.

Coat

Expose Develop

Sputtering Dispense

Glass In

Upper

layer

_Repair

Insp Coat

Dry Dry

Cleaning ^{PR Coating}

Dry Fire

Expose Develop Etch/Strip

Fire Fire

Fire

P layer Glass In U layer D electrode D layer Rib

Fire Dry Coat

Cleaning Dry(R)

Expose Develop

Expose Coat(G)

Dry(G)

Develop Coat(R)

Coat(B)

Expose Develop

Fire Dry(B) Dry

Coat

Expose Develop

Repair Insp Fire

Coat Coat

Dry Glass In

Lower layer

Dry

DFR Lami.

Fire

Expose

Strip Develop Sandblast

Fire

(24)

• 3-dimensional

• Time dependent

• Squeezing flow

(pseudo steady state)

• Non-isothermal

(temp distribution with time and position)

• Curing reaction

• Particulate flow

• Complex flow field and geometry

particle and stress distributions

typical rheology problem

(25)

PP/clay

Electric field

Exfoliation

+

II

MRC 2003

Nanorheology

Why? What happens?

(26)

•PP/Clay E2

•PP/Clay

Optics measured at 180C. (x 100)

layer-stacking destruction

separation of silicate layers

(27)

(28)

(29)

(2D)⏐ 27Apr2003⏐G-NewtonFluidSimulationattime .00

0 1 2 3 4

X -3

-2 -1 0 1

Y

(2D)⏐ 27Apr2003⏐G-NewtonFluidSimulationattime .00 (2D)⏐ 27Apr2003⏐G-NewtonFluidSimulationattime .00

0 1 2 3 4

X -3

-2 -1 0 1

Y

0 1 2 3 4

X -3

-2 -1 0 1

Y

0 1 2 3 4

X -3

-2 -1 0 1

Y

(2D)⏐ 27Apr2003⏐G-NewtonFluidSimulationattime .00

Simulation & modeling

(30)

Flow past a confined cylinder

We

0.1 0.3 0.5 0.7 0.9 1.1

0.0 0.2 0.4 0.6 0.8 1.0 1.2

Dimensionless Drag

116 118 120 122 124 126 128 130 132 134

Liu et al. (1998) : DEVSS-G/SUPG Fan et al. (1999) : h-p FEM

Alves et al. (2001) : FVM

Caola et al. (2001) : RK4+DEVSS-G/DG

Owens and Chauviere (2002) : Sprectral Method UM2

UM4

(31)

chain

dumbbell

(32)

Modeling: BD, DPD, FPD, LB,…

(33)

( )

2 , , , ,

Re (1 )

0 p p

p

f

u u u p u

t u

τ λ β η

β τ

τ

=

⎛ ∂ + ⋅∇ ⎞ = −∇ + ∇ ⋅ + − ∇

⎜ ∂ ⎟

⎝ ⎠

∇ ⋅ = u

Critical to precise process control

- precision injection, coating, micro-channel flow …

(34)

• Separation of long DNA molecules in a

microfabricated entropic trap array, Science, 2000.

Elongational Index

Ch 01

Introduction to complex fluids

Solid --- Liquid

Ideal Solid --- Most Materials --- Ideal Fluid

Elastic --- Viscoelastic --- Viscous

Strain

0 time

Stress

0 time

Stress

0 time Stress

0 time

Solid Like --- Liquid Like

Ideal Solid --- Most Materials --- Ideal Fluid

Purely Elastic --- Viscoelastic --- Purely Viscous

γ

τ = G τ = η γ &

( )

( ( )

)

We u

u

u u u

t

τ + ⎛ ⎜ ⎝ ∂ ∂ τ + ⋅∇ − ∇ τ ⋅ − ⋅∇ τ τ ⎞ ⎟ ⎠ = β ∇ + ∇

( )

2

, , , ,

Re (1 )

0

p p

p

f

u u u p u

t u

τ λ β η

β τ

τ

=

⎛ ∂ + ⋅∇ ⎞ = −∇ + ∇ ⋅ + − ∇

⎜ ∂ ⎟

⎝ ⎠

∇ ⋅ =

u

Time-dependent Viscoelastic Behavior

Old Testament Prophetess who said :

"The Mountains Flowed before the Lord"

Everything Flows if you wait long enough!

Deborah Number, De - The ratio of a characteristic time of a material (τ) to a characteristic time of the process (Τ)

De = τ/Τ

Rheology

• The science of flow and deformation of matter (complex fluids)

• Viscoelastic

• Deborah number

• Processing technology

De = τ/Τ

Mathematical rheology Mathematical theology

ABS

ABS (Acrylonitrile-Butadiene-Styrene)

Particle

size Gel

content Graft

ratio Impact

strength Hard-

ness Tensile

strength Flexural

strength VST gloss

ABS-4 3075 86 42 26.7 96.4 402 582 93.7 103.9

ABS-5 3100 82 69 24.1 95.3 393 567 95.1 101.7

G’ and η* of ABS

G’ vs. graft ratio

Sheet grade 礱獺

(沁茿梞 汬籤艃 ABS)

Competition with HIPS

Kingdom of rheology

14 th ICR, Aug.22-27, Seoul

• Computational rheology

• Flow instability

• Foams, emulsions & surfactants

τ = G τ = η γ _&

τ + ^⎛ ⎜ ⎝ ^∂ ∂ τ + ⋅∇ − ∇ τ ⋅ − ⋅∇ τ τ ^⎞ ⎟ ⎠ = β ∇ + ∇

(沁茿梞汬籤艃 ABS)

14 ^th ICR, Aug.22-27, Seoul