UNIVERSITY OF WALES INSTITUTE OF NON-NEWTONIAN FLUID ...

UNIVERSITY OF WALESINSTITUTE OF NON-NEWTONIAN FLUID MECHANICS

CONFERENCE ON INDUSTRIAL RHEOLOGY

Hoole Hall Hotel, Chester5 - 7 April 2004

PROGRAMME

27. Mar. 2004

PROGRAMME

Monday 5 April - Afternoon

12:30 Lunch

Session 1 Chairman: K Walters

14:00 - 14:40 D V BogerSomething old , something new, and something very new in industrial rheology

14:40 - 15:20 J R A PearsonThe role of diffusion in non-Newtonian fluid mechanics

15:20 - 15:45 D R OliverSimultaneous shear and squeezing flow applied to a ceramic paste

15:45 - 16:15 Coffee/Tea

Session 2 Chairman: K Walters

16:15 – 16:45 I EmriThe effect of boundary conditions on structure formation of PA fibers

16:45 - 17:15 G N GreavesSolid state rheology of zeolites under thermobaric stress

17:15 - 17:40 B DebbautThe double convected pom-pom model: a numerical validation for the contraction flow

17:40 - 18:05 E I FrenkinThermophysical characteristics of PP/LCP blends under high pressure

19:30 Dinner

27. Mar. 2004

PROGRAMME

Tuesday 6 April - Morning

Session 3 Chairman: M H Wagner

09:00 - 10:00 H M LaunThirty years of industrial polymer rheology at BASF

10:00 - 10:25 P MoldenaersMorphology development of two-phase blends during capillary flow

10:25 - 10:55 Coffee/Tea

Session 4 Chairman: M H Wagner

10:55 - 11:35 C GallegosRheology of recycled-EVA modified bitumen

11:35 - 12:05 M P EscudierExperiments and numerical simulations of laminar viscoelastic flow throughsudden expansions

12:05 – 12:30 J M MaiaInfluence of the operating conditions on the gelatinisation of rice flour during extrusion

12:30 - 14:00 Lunch

27. Mar. 2004

PROGRAMME

Tuesday 6 April - Afternoon

12:30 – 13:45 Lunch

Session 5 Chairman: A R Davies

13:45 - 14:40 H A BarnesThirty years of industrial dispersion rheology at Unilever

14:40 - 15:20 J-M PiauMacro and micro rheometry of carbopol gels

15:20 - 15:45 H P HürlimannA new multipass-type polymer compounding machine approaches industrial application

15:45 - 16:15 Coffee/Tea

Session 6 Chairman: A R Davies

16:15 - 16:55 D G BairdRheology of highly filled polymers using squeezing flow

16:55 - 17:35 M H WagnerMelt rheology of industrial polymers: relating stress to strain and energy

17:35– 18:00 O KulikovThe use of thermoplastic and raw elastomers to delay the melt fracture onset in extrusion of polyethylene

19:00 for 19:30 Conference Dinner

27. Mar. 2004

PROGRAMME

Wednesday 7 April - Morning

Session 7 Chairman: P Townsend

09:00 - 09:40 G C MaitlandComplex fluids for hydrocarbon recovery - rheology in extremus

09:40 - 10:20 R KeuningsThe CRAFT tube model: a new constitutive equation for blends of entangled linear polymers

10:20 - 10:45 Ch BaillyPrediction of linear viscoelastic properties from molecular structure for blends of linear and x entangled polymers

10:45 - 11:15 Coffee/Tea

Session 8 Chairman: P Townsend

11:15 - 11:40 F T PinhoOptimisation of profile extrusion dies: numerical and experimental work

11:40 - 12:00 F Chinestraα-NEM and model reduction: two new and powerful numerical techniques for simulating complex flows

12:00 - 12:30 O WallevikRheology of coarse particle suspensions such as fresh concrete

12:30 End of Conference

27. Mar. 2004

Experiments and numerical simulations of laminarviscoelastic flow through sudden expansions

M P Escudier1, P J Oliveira2, F T Pinho3, A Afonso3 and R J Poole1

1Department of Engineering, University of Liverpool, UK2Departmento de Engenharia Electromecanica, Universidade da Beira Interior,

Portugal3Departamento de Engenharia Mecanica, Universidade do Minho, Portugal

Industrial Rheology Conference, Hoole Hall, Chester, UK. April 5th –7th 2004

Outline

• Introduction

• Expansion geometry

• Fluid Rheology

(Shear rheology, N1, extensional viscosity)

• Approach flow (smooth contraction)

• Downstream flow (sudden expansion)

• Conclusions

Introduction

• Experimental and numerical investigation of laminar viscoelastic fluid flowthrough a plane sudden expansion of expansion ratio (D/d) 1.43 and aspectratio (w/h) 13.3.

Why?• Investigate viscoelastic fluid flow in a basic geometry which exhibits

interesting fluid-dynamic behaviour.

• Extend previous studies (Re < 1) to higher Reynolds numberswhere inertia starts to play an important role.

• Are there qualitative changes compared to Newtonian fluidflow? Is the flow 2D?

• Extend previous studies by providing L.D.A velocity data forquantitative comparisons with numerical simulations.

Experimental arrangement

Area ratio R = d/D = 0.7

Upstream spanwise profiles (x-z plane)

at x/h=-8.33 and 0

d = 28mm, h = 6mm,

D = 40mm, w = 80mm

Fully-developed inlet flow through a square duct 80mm x 80 mm (120 DH development length)

(area ratio > 2/3 ! double backward-facing step )

Downstream profiles at 0<x/h<10 in x-yplane

Aspect ratios A1 = w/h = 13.3

A2 = w/d= 2.86

RheologyFluid: Polyacrylamide (PAA) Seperan AP 273 E 0.05%, 0.1% 0.4% w/wincluding Carreau-Yasuda (5-parameter) model fits

c

BhUµ

!=Re

hUB

C =!!

Figure 2.4: Viscosity versus shear rate for various concentrations of polyacrylamide(including Carreau-Yasuda fit)

Shear rate (1/s)

Viscosity(Pas)

10-3 10-2 10-1 100 101 102 103 10410-3

10-2

10-1

100

101

102

0.05%0.1%0.4%CY fit

!c

Rheology

Fluid: Polyacrylamide (PAA) Seperan AP 273 E 0.1%, 0.4% w/w

! (Pa)

Firstnormalstressdif fere nceN1(Pa)

100 101 102101

102

103

0.4%PAA

0.1%PAA

N1 = a!b

! (Pa)

N1/2!

100 101 102

100

101

0.1%PAA

0.4%PAA

N1/2! > 0.5

Extensional rheology

Fluid: Polyacrylamide (PAA) Seperan AP 273 E 0.05%, 0.1%,0.2% and 0.4% w/w

Thermo Haake CaBER Extensional rheometer

0

200

400

600

800

1000

1200

1400

1600

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45

% concentration of PAA (w/w)

Ext

ensi

onal

vis

cosi

ty (

Pa.

s)

EXTµ!µ0µ

Extensional rheology

160 000915069.371620.4

115 0004110879.4426.60.2

125 000635484.378.830.1

165 0007604662.820.6140.05

(Pa.s)(mPa.s)(Pa.s)c

(%)0µ

µEXT!µ

µEXT

Results: Flow through smooth contractionSpanwise variation of streamwise velocity (U/UB) profiles within smoothcontraction 0.05% PAA and 0.1% PAA Re " 120

Figure : Spanwise variation of mean streamwise velocity ( U/UB ) profiles for 0.1% PAA

z / w

U/UB

0 0.25 0.5 0.75 10

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

NewtonianCarreau-YasudaPTT

x / h = 0

0.1% PAA

x / h = -8.33


z / w

U/UB

0 0.25 0.5 0.75 10

0.2

0.4

0.6

0.8

1

1.2

0

0.2

0.4

0.6

0.8

1

1.2

NewtonianCarreau-YasudaPTT

x / h = 0

0.05% PAA

x / h = -8.33


z / w

U/UB

0 0.25 0.5 0.75 10

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

0.4% PAANewtonianCarreau-YasudaPTT

x / h = 0

Results: Flow through smooth contraction


z / wU/UB

0 0.25 0.5 0.75 10

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

PTT0.4% PAA

y/D = 0.3

x / h = 0 y/D = 0.5

y/D = 0.4

y/D = 0.20

y/D = 0.25

Spanwise variation of streamwise velocity (U/UB) profiles within smoothcontraction 0.4% PAA Re " 5

Results: Flow downstream of expansionStreamwise velocity (U/UB) profiles downstream of expansion for 0.05% PAA Re=120

Figure : Streamwise velocity ( U/UB ) profiles for 0.05% PAA Re =185

y/D

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

Newtonianx/h0 1 2 3 4

1U = 0

PTTCarreau-Yasuda


Figure : Mean streamwise velocity ( U/UB ) profiles for 0.05% PAA

y/D

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

Newtonianx/h5 6 8 10

1

7

U = 0

XR = 7.5

PTTCarreau-Yasuda



y/D

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

PTTx/h0 1 2 3 4

1

U = 0

XR = 2.3

Newtonian Carreau-Yasuda



y/D

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

x/h5 6 7 8 10

1

Newtonian PTTCarreau-Yasuda



y/D

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

PTT0 1 2 3 4

1

x/h

No recirculation

Newtonian Carreau-Yasuda



y/D

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

x/h6 10

Newtonian

1

PTTCarreau-Yasuda

Conclusions

Flow through smooth contraction• Flow becomes increasingly three-dimensional (but symmetrical about x-y

centreplane) and complex with increasing concentration.• Simulations fail to predict velocity overshoot near side-walls.

Flow over double backward-facing step• Flow symmetrical about x-z centreplane.• 0.05% PAA flow predicted reasonably well by PTT model (consequence of

flow being more two-dimensional?)• 0.1% and 0.4% PAA profiles not predicted well by any model (consequence

of poor agreement through contraction and hence inlet velocity profiles?)• PTT model corrects shear-thinning “over-prediction”

Latest experimental study


z / wU/UB

0 0.25 0.5 0.75 10

0.2

0.4

0.6

0.8

1

1.2

0

0.2

0.4

0.6

0.8

1

1.2

x / h = 0

x / h = -3.33

x / h = -1.67

x / h = -1

Plane sudden expansion

d = 10 mmD = 40 mmh = 15 mm

R = d/D = 0.25 (< 2/3)A = w/h = 5.33 (<10)

0.05% PAA Re " 200

Spanwise variation of streamwise velocity(U/UB) profiles within smooth contraction

0.05 % PAA (x-z centreplane)

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