Slide 1

Task II Presentations

Task II Overview – Morley

3D Modeling Benchmarks – Smolentsev

HIMAG Status - Munipalli

APEX Electronic MeetingFebruary 2, 2003

Slide 2

Modeling1D/2D/3D Modeling Development and Testing

HIMAG Development and Testing

ExperimentsMTOR (shared with Task I)

FLIHY (& Jupiter-2)

Papers for APEX Report“Modeling and experiments for liquid metal free surface MHD flow”

“Modeling and experiments for turbulent free surface flow and heat transfer”"On the choice of dependent variables in modeling LM-MHD flows for fusion

applications”

Task II Activities and Papers

Slide 3

3D MHD Modeling Summary

• Benchmark problems (Smolentsev)– MHD Lid-driven cavity

• HIMAG progress (Munipalli)– Inclined-plane in field gradient – NSTX jet

• DiMES modeling • Telluride workshop (Ni)• Fluent 6.1 with MHD beta-package being

used at UCLA

Slide 4

x

y

0 25 50 75 1000.84

0.86

0.88

0.9

0.92

0.94

0.96

0.98

1

Green Line: 40x200 Meshes for NonMHD FlowBlue Line: 40x200 Meshes for MHD FlowCyan Line: 80*200 Meshes for MHD Flow

x

y

0 25 50 75 1000.84

0.86

0.88

0.9

0.92

0.94

0.96

0.98

1

red line: nonmhd flow with Re=123.5 driven by gravity forceblue line: mhd flow with Ha=28.84, Re=123.5 driven by gravity force

B formulation is solvedheight function method is used for the interfacial flowparabolized navier-stokes equation is simulated

Level set method and electric potential poissonequation from HIMAG

VOF method + B formula

height function method and B formula

Re=123.6, Ha=28.84, density ratio=0.001, viscosity ratio=0.001, conductivity ratio=0

X

Y

0 25 50 75 1000.84

0.86

0.88

0.9

0.92

0.94

0.96

0.98

1

From Neil Using VOF+B formula

Inclined plate two-fluid mhd and non-mhd flows

Slide 5

DiMES Experiment Proposal

• Heated Li sample• Insulated cup• Mesh restraint• Electric current diagnostics• Biasing• 3D Modeling

Slide 6

Current Status FLIHY Heat Transfer Experiments

• New heat transfer enhancement experiments with span-wise cylinders

• New curved test section ready for construction

Water Film flowing under IR heater

FlowHeat Flux

Slide 7 Heat Transfer Enhancement by streamwise riblets

Smooth Modified

0.1 4.0 10000 0.94 2.2 1.8 3.47 2.67 30%

3.5 5.8 14500 25 1.0 7.2 2.38 1.05 127%

3.5 9.7 24250 52 0.9 7.2 2.24 1.03 117%

50 10.4 26000 320 0.6 21.7 1.99 1.16 72%

75 15.0 37500 723 0.5 28.2 2.21 2.15 3%

Improvement in surface

temperature drop (%)

mean surface temperature

differnce (Ts-Tb)

Inclination angle

(degrees)

Flow rate (l/s)

Reynolds number

Froud Number

Mean height (cm)

surface deformation

ratio (%)

Slide 8

Drain

Support FrameFLIHY – Proposed Curved Hydrodynamic Test Section

Flow 3D Model3D analysis showing exit velocity profile.

Nozzle is symmetric along the X-Y plane

• Assess free surface fluid flow behavior along curved surfaces -degree of uniform flow thickness and occurance of hydraulic jump phenomena

• Study surface waviness throughout the flow channel.

• Study flow behavior around penetrations

Slide 9

11 cm

15 degrees angle

30 degrees

Z=17.404,X=30.857,

R= 7.594

R= 3.6

Z=3.7,X=8.66,

R=49.14

X=18, Y=53.14

R=49.14

R=32

X=18, Y=-32

R=32Y=0

R=7.4833

X=31, Y=-11.492

X=40.1, Y=9.645

R=15.492

Curved Hydrodynamic Test Section –Nozzle Design using FLOW3D

Slide 10

Thermofluid Task Schedule for 6 year collaboration

FuY 2001 FuY 2002 FuY 2003 FuY 2004 FuY 2005 FuY 2006

ThermofluidFlowExperiments

Facility:FLIHY-Closed(UCLA)

Non-magnetic Phase Magnetic Phase

Check &Review

Turbulence Visualization Experiments

Heat Transfer Experiments

Pipe flow geometries with innovative heat transfer enhancement configurations

Continue with heat transfer, or another option

Check &Review

Continue with MHD, or another option?

Turbulence Visualization Experiments

Heat Transfer Experiments

Same geometries as 2001-03 with magnetic field

IntegratedFLIBE

Experiment?

Check &Review

Flibe Loop, or another option?

Slide 11

Acrylic

0 ft 5 ft 10 ft 15 ft 20 ft 25 ft

MixingTank

•• •• •• ••••••

Power Controller

Polished SS304 Pipe (D = 3.5 inch)

Acrylic FlowStraightener

AcrylicWater Box

Band Heater, 120 V max, 1250 W max

304 SS Pipe Wall

Pipe

Copper Interlayer

T-type TC, 0.02 in diameter304 SS sheathed, ungrounded

304 SS Pipe Wall

Pipe

Water Box

Pipe Centerline

Machined Smooth

Epoxy JointWeld

O-Ring

FlangeBolt

roughly to scalePipe Centerline roughly to scale

TraversingTC Probe

TC Multiplexer

•

FusedJoint

Straight Pipe Heat Transfer and PIV Test Section

Slide 12 MTOR

• Task I MHD film and droplet experiments

• Ultrasound testing in quasi-2D test section

Slide 13

Flowmeter Calibration Tests

MTOR Flowmeter Calibration

lit/sec = 0.1701*mVR2 = 0.9999

0

0.2

0.4

0.6

0.8

1

1.2

0 0.05 0.1 0.15 0.2

liters/second

flow

met

er s

igna

l (m

V)

calculated calibration

• Data from 2D test section seemed inconsistent with models

• Flowmeter calibration using discharge technique showed analytic expression was incorrect

• New flowmeter calibration constant applied to old data

Slide 14

Checking Russian Data on Properties

Property Measurements

3.25E+06

0.45445

6333.1

measured

-0.62%3.27E+06V,I on biased capillary

tube

22 CElectrical conductivity(Ω-1m-1)

33.58%0.3402Cannon-Fenske

Viscometer

22 CViscosity(10-6 m2/s)

-0.44%6360.9Weighed graduated cylinder

22 CDensity(kg/m3)

deviationRussianmethodtempProperty

Slide 15

2D Inclined-Plane Test Section

• 300 A (~106 A/m2) available for magnetic propulsion tests

• 7 Ultrasonic Flow Height Transducers

• Variable inclination

• Flow area: 20 cm x 60 cm(wide to keep Haβ small)

• Various wall types: insulated, coated, metallic

Slide 16

LM In LM OutElectrode

Electrode

Ultrasound Transducer

B

Experiments for 2D Inclined Plane Flow with Magnetic Propulsion

Free SurfaceNozzleHCl bath

Flow Spreader

Slide 17

Dynamic flow height measurements using ultrasound technique

to 100 MS/s DAQ – height resolution ~27µm

-0.5-0.4

-0.3-0.2-0.1

0

0.10.20.3

0.40.5

0.0E+00 5.0E-06 1.0E-05 1.5E-05 2.0E-05

pulseinitiation

reflection from acrylic-LM interface

reflection from LM free surface

LM

Acrylic

Transducer

time-of-flight

height = speed-of-sound*(time-of-flight/2)

(speed-of-sound for ga alloy measured 2740 m/s)

Slide 18

Both B field and Magnetic Propulsion current act to reduce film thickness

Film

Hei

ght (

m)

0.E+001.E-032.E-033.E-034.E-035.E-036.E-037.E-03

1 2 3 4 5 6 7

No field

Bmax = 0.5

Imp = 160A

Imp = 258A

Q = 0.15 l/sθ = 0.3°Re = 1711Hamax = 85

each point is average of ~50 points taken over 1 sec

Averaged Height Data –Subcritical Flow, No nozzle

Probe number (distance from inlet, 6 cm separation)

Slide 19

Magnetic propulsion effective, but data also shows some instability

0 .E+00

1 .E-03

2 .E-03

3 .E-03

4 .E-03

5 .E-03

6 .E-03

0 1 2 3 4 5

Time (s)

He

igh

t (m

)

B = 0 T

B = 0 .18 T

B = 0 .31 T

B = 0 .31 T, Imp = 210 A

2mm nozzle followed by hydraulic jump, Subcritical Flow

Q = .15 l/sθ= 0.5°Re=1711Halocal≈40

• B-field acts to laminarize flow – Reducing flow resistance and surface waves

• Presence of magnetic propulsion current triggers surface wave with ~1 s period

data from probe 4, 22 cm downstream from nozzle

Slide 20

Why does presence of magnetic field lead to acceleration of flow?

0

1

Y / h

• In most cases the ratio Ha/Re > 0.008, which for pipe flows is an approximate cutoff above which turbulence is suppressed.

• Flow is elongated in field direction so that only small drag coming from Hartmann layers

• Transverse current flow mostly acts to accelerate liquid, except very near inlet (inside the nozzle), property of 1/R magnetic field which has no inflection point.

• Gradient is not strong enough to modify velocity profile significantly so that velocity profile is still nearly low shear laminar parabolic.

decelerating current

accelerating current

B B

Slide 21

Other observations • Complete channel filling was a problem for the non-wetted channel,

especially at larger inclination angle. Magnetic propulsion current however forced channel filling. Channel wetting also eliminated channel filling issue.

• Initial conditions with Fr both greater than (supercritical) and less than (subcritical) unity were explored, but in all initially supercritical cases up toflowrate Q = ~0.2 l/s, the flow experience a hydraulic jump near the nozzle exit and became subcritical for the remainder of the flow.

• The degree of turbulence suppression and presence of magnetic propulsion current was not enough to inhibit the formation of a hydraulic jump near the nozzle exit for low flowrate cases

• The ultrasound technique proved effective with gallium alloy flows described above, but the signal behavior was erratic, sometimes disappearing and reappearing with no good explanation. Cleaning with HCl aided in getting good ultrasound signal

Slide 22

1.0E-03

1.5E-03

2.0E-03

2.5E-03

3.0E-03

3.5E-03

4.0E-03

1 2 3 4 5 6

Probe Number

flo

w h

eig

ht Height data with no field

compared well to Bernoulli model with f = 0.4 (shown) and k-e data (not-shown)

Q = .278 l/sθ= 1°Re=3088Ha=0

B = 0 T at nozzle exit

2mm Nozzle Supercritical Turbulent Flow

Slide 23

1.0E-03

1.5E-03

2.0E-03

2.5E-03

3.0E-03

1 2 3 4 5

Probe number

flo

w h

eig

ht

B = 0.45 T at nozzle exitB = 0.29 T at probe 5

Height data at max field compared to Bernoulli model with fully laminar to fully turbulent transition at Ha/Re ~ 0.007– flow is not fullylaminarized.

Q = .278 l/sθ= 1°Re=3088Ha=40-20

2mm Nozzle Supercritical MHD-Laminarized Flow

Slide 24

flowdirection (m)

heig

ht(m

)

0.05 0.1 0.15 0.2 0.25 0.3

0.001

0.002

0.003

0.004

0.005

Averaged MTOR data

1D model

2mm Nozzle Supercritical MHD-Laminarized Flow

Contour plot shows 2D VOF laminar model result

Slide 25

2mm Nozzle Supercritical MHD-LaminarizedFlow with Magnetic Propulsion

1.0E-03

1.5E-03

2.0E-03

2.5E-03

3.0E-03

3.5E-03

4.0E-03

1 2 3 4 5 6

Probe Number

Flow

Hei

ght (

m)

B = 0.45 T at nozzle exitB = 0.29 T at probe 5Iapplied = 237 A

Q = .278 l/sθ= 1°Re=3088Ha=40-20

Height data at max field compared to Bernoulli model with purely laminar flow –experimental data shows flow is not accelerated until probe 6?

Slide 26

Magnetic propulsion instability not seen in supercritical MHD Free surface flow

1.0E-03

1.5E-03

2.0E-03

2.5E-03

3.0E-03

0.0 0.8 1.6 2.4 3.2 4.0 4.8

Time (s)

flow

hei

ght (

m)

I=2000I=3400IMP=170IMP=237

Slide 27

Future Plans for quasi-2D test sectionfilm flow experiments

• A detailed comparison of the quantitative data acquired form this experiment to the 2D and 3D numerical models still needs to be performed

• Exploration of effects from 3D fields, and expanding/contracting wall area.

• Testing of MetFlow ultrasonic velocimeter device to see how well it can be used for free surface measurments.