Scientific Design of Large Scale Thermal-Hydraulic Test Facility in KAERI

Tae-Ho LeeTae-Ho Lee

International Conference on Fast Reactors and Related Fuel Cycles –Challenges and Opportunity (FR09)

Kyoto, Japan10 December 2009

2

Outline

IntroductionI

Design Requirements II

Preliminary Design FeaturesIII

Validation WorksIV

SummaryV

3

Objectives and Plan

< Layout of Experimental Facility >

�Objectives

- Verification of passive decay heat removal

design concept

- Assessment of initial- & long- term cooling

capability by natural circulation

- Database construction for verification of

system analysis code

�Test Plan

- Preliminary design based on KALIMER-600

(’09)

- Major Component test (’09-’11)

- Basic design based on demonstration reactor

(’11)

- Detailed design (‘12)

- Installation (’13)

- Start-up test (’14)

- Performance experiment (’15~)

Reactor

Vessel

AHX

IHX Gas Cooling System

Sodium Purification System

PDRC

SDT

Gas Supply System

4

Passive Decay Heat Removal Design Concept

� System Design Features

- Elimination of active components

- Operation by natural circulation

- No operator action

- Major components

• AHX, DHX and piping

� System Operation

- Normal operation

• Partially immersed Decay Heat

Exchanger (DHX) in cold sodium pool to

prevent sodium solidification in PDRC

loop

� Optimization between immersed depth

and heat loss

- Primary pump trip

• Decay heat removal by natural

circulations in PDRC & PHTS

Normal Normal operationoperation

PHTS pump PHTS pump shutdownshutdown

< PDRC design concept >

5

Design Requirements

�Top-Tier Requirements

- Preservation of overall system behavior in prototype plant

- Reproducibility of major T-H phenomena

- Consideration of economics: Initial cost

�Consideration for Design requirements

- Selection of key test matrix from the analysis of design basis events

- Identification of important T-H phenomena for each key test matrix

- Determination of major constitutive components to be simulated

- Measurement requirements

�Design Requirements (Preliminary Design)

- KALIMER-600 as a reference plant

- Volume scale: 1/125, Height scale: 1/5

- Prototypic working fluid and temperature

- 7% of the scaled nominal power

- Simulation of representative accidents and transients

6

Scaling Method Applied

�3-Level Scaling Method (Ishii et al.)

-1st level : Global scaling (Integral system scaling)

-2nd level : Mass & energy inventory, and boundary flow scaling

-3rd level : Local phenomena scaling

-Suitable for preserving the natural circulation phenomena in reduced-height scale

facility

�Key Design Parameters from Global Scaling Criteria

DesignDesign

1/2.24 lR1/2Time

2.24 1/ lR1/2Power/volume

1/2.24lR1/2Velocity

1 1Temperature distribution

1lR/aR1/2

Aspect ratio1/125aR lRVolume

1/5lRPressure drop1/25 aR (=dR2)Area

1/55.9 aR lR1/2Mass flow rate 1/5 dRDiameter

1/55.9 aR lR1/2Core power1/5 lRLength

Scaling

LawParameters

Scaling

LawParameters

7

Overall Facility Configuration

�Main systems

-PHTS

• Reactor vessel & internals,

Core simulator, 4 IHXs, 2 PHTS pumps

-PDRC

• 2 DHXs, 2 AHXs, Exp. tank

�Auxiliary Systems

-Sodium purification system

- IHX gas cooling system

-Heat loss compensation system

-Power supply system

-Gas supply system

-Fire protection system

�Instrumentation/Control/Monitoring

System

8

Reactor Vessel & Internals

� Same Configuration with Prototype

� Design Conditions

- Design Temperature: 600 oC

- Design pressure: 1 MPa

- Code: ASME Sec. VIII Div.2

� Local Phenomena of Major Concern

- Pressure loss

- Heat loss and accumulation

- Heat transfer through solid walls

- Temperature and flow distribution

- Free surface behavior

- Local natural convection inside DHX

barrel

- Sodium inventories at hot & cold pool

and buffer region

- Relative height of internal structure 1/5 76***380Total Pressure Drop [kPA]1/55.9 138.37731.3System Flow Rate1545545Core outlet Temperature [oC]1390390Core Inlet Temperature [oC]111System Pressure [bar]

Scale [M/P]ModelPrototypeParameter

< Operating parameters at nominal condition >

3.74 m

2.32 m

9

Yellow: Inner coreOrange: Middle coreRed: Outer coreBlack: Unheated rodBlue: Bypass regionGray: Solid structure

Reactor Core Simulator

� Simulate 7% of the Scaled Full Power (1.9 MW)

� 3 Different Groups (IC, MC, OC) of Power Level

� Major Phenomena of Concern

- Pressure loss through core

- Fraction of each group power and flow rate

� Heater Rod Diameter and Arrangement

- Consider the geometrical scaling criteria for each group flow area & core height,

space for instrumentation, assembly arrangement, cost

29 mm

Heater Diameter

106

84

122

No.

5.3 kW (max. 7.5)3

7.4 kW (max. 7.5)2

6.0 kW (max. 7.5)1

Capacity of each heater

Heater Group

10

Heat Exchangers (IHX, DHX, AHX)

� Design Considerations

- Same configurations and materials with the heat exchangers of a prototype

- Preserving overall heat transfer coefficient and log-mean temperature difference

- Satisfying the similarities for heat capacity, flow rate and pressure drop

- Heat transfer tube ID/OD: Minimization of distortions for major dimensionless groups

related with heat transfer

1379

.0 m

m

1603

.6 m

m

DHX outflowbaffle

DHX inletnozzle

Cold sodiumdowncomer

Lower tube sheet(flow distribution)

Heat transfertube

tube-sidesodium out

Upper sodiumchamber

DHX shroud

CL

tube-side

sodiumin

749.

0 m

m

799.

0 m

m

50.0 mm

Heat Transfer Tube Ntube = 16 EA OD = 13.4 mm t = 2.2 mm

ID = 169.0 mm

OD = 118.0 mm

135.

0 m

m

934.

0 m

mRain Protection Cap

Heated Air Outlet

Air Stack

Hot Sodium Header

Cold Sodium Header (Storage Tank)

Cold air inlet

Air Guiding Baffle

AHX Annulus(air passage)

Sodium in Sodium out

Upper tube Sheet

Lower tube Sheet

0.03 m

0.0159 m

0.01 m

0.482 m

0.05 m

IHX DHX AHX

11

PDRC Piping

�Design Considerations

-Same piping configuration as that of

a prototype

-Preservation of relative elevation

-Minimization of pressure loss and

inventory distortions

�Design Parameters

1/51/5.2176920Total pressure loss (Pa)1/51/5.05.1225.4Dist. between DHX & AHX (m)1/51/5.469373Pressure Loss (Pa)1/51/4.478345Pipe I.D. (mm)Cold Leg

1/51/5.1107547Pressure Loss (Pa)1/51/3.9102395Pipe I.D. (mm)Hot Leg

Ideal Ratio

Ration[M/P]ModelPrototypeParameters

12

Auxiliary Systems

T I

02

T I

01

LG

01

PG

01

T I

03

TIC

01

TIC

02

TIC

04

T I

04

T I

05

T I

06

TIC

03

TIC

05

TIC

06

T I

07

TIC

07

T I

08

TIC

08

PG

02

LG

01

Gas Vent

Gas Vent

Gas Vent

� IHX Gas Cooling System

- Provide the initial and boundary conditions for accident simulation

- 2 loops (1 loop for 2 IHXs) with N2 cooling fluid

� Sodium Purification System

- 17 tons of sodium

- Storage tank, Cold trap, Plugging meter, EM pump, etc

� Heat Loss Compensation System

- Heaters with a total capacity of 117 kW and Insulation material for total 34 regions

� Power Supply System

- 4.5 MW capacity

� Gas Supply System

- Provide service gases such as N2, Ar, air

� Fire Protection System

- 2-wire sodium leak detector, Catch pan, Fire Extinguishing equipment

< IHX gas cooling system >

< Sodium supply/purification system >

13

AHX

DHX

Sodium Storage Tank

Meas. Develop. Loop

Sodium Purification System

Gas Supply System

Mech. Pump

IHX

Major Component Performance Test

�Objectives

- Verification of heat exchanger (IHX,

AHX, DHX) design codes

- Demonstration of mechanical sodium

pump performance

- Development or Improvement of

sodium flow measuring techniques

�Schedule

- Design (’09)

- Installation (’10)

- Test (’11~)

�Major Characteristics

2.5 MW

600 oC30 kg/s1.1 MWt

Overall dimension(W[m] x L[m] x H[m])

SodiumPump HeadPump flow capacity

43 mMax. flow through HX11 tonMax. sodium temp.

182 kg/sHeat capacity of HX

14x10x20Req. electric power < Overall test loop layout >

14

In-Vessel Thermal-Hydraulic Test Using Water� Investigation of Temperature and Flow Distribution

Inside Reactor Vessel with a Flow Visualization

�Verification of Multidimensional Analysis Method

�Development of Local Flow Measuring Methodology

�Design & Fabrication (’09-’10), Experiment (’11)PlexiglassRV material

WaterWorking fluid

1/10Scale

1.0Time ratio

0.1Velocity ratio

1.0Ri

14.6△△△△T across core [oC]

1.14RV diameter [m]

1.85RV length [m]

KALIMER-600

Referencereactor

ModelParameter

15

Thermal Hydraulic Analyses

�3D-CFD analysis for reactor pools

of KALIMER-600 & facility

-Assessment of the similarity of

multi-dimensional distribution

inside reactor vessel

-Analysis model

• Half symmetry

• Porous models for core, IHX & DHX

• Conjugate heat transfer

• ~9 million polyhedral meshes

• Results at full power condition for

KALIMER-600

�Using system analysis code MARS, Scoping Analyses are

Under way

-Validation of overall scalability for major accident scenarios

-Validation of local phenomena scalability for major T-H

hydraulic phenomena

- Identification of design parametric effects such as heat

structure, design dependency, etc

16

Summary

�Preliminary Facility Design as a Reference Reactor of KALIMER-600

was Introduced.

- Scoping analyses using system code & CFD are on-going to assess the

validity of the preliminary design methodology

�Design Based on the Demonstration Reactor will Start at 2011 and the

Facility is Scheduled to be Constructed by the End of 2013.

�Currently, Major Component Performance Test Loop is Under

Development.

- Heat exchangers and mechanical pump tests will start from 2011