RELAP5-3D AT THE INL

RELAP5 International Users Group Meeting

and Seminar

Salt Lake City, Utah

July 25-28

J. R. WOLFRELAP5-3D

PROGRAM MANAGER

RELAP5-3D History

• Models transient fluid flow in user-defined thermal-hydraulic networks

• Most widely used water-cooled nuclear reactor accident analysis code

• Traces roots back to the very beginning of nuclear power plant simulations

• Early codes were “node and branch”,RELAPSE1 and RELAP2

• True loop analysis capability began in 1970 with RELAP3

RELAP Has Had a Continuous History of Development at the INL

• T/H codes at INL derived from Bettis FLASH-1 code (1966)• RELAP1 through RELAP3 (1968 -1973 )• RELAP4 (1973 – 1981)• RELAP5 (1979 – 1995)

– MOD 0 (1979)– MOD 1 (1982)– MOD 1.5 (1982)– MOD 2 (1985)– MOD 2.5 (1989)– MOD 3 (1990)– MOD 3.1 (1993)– MOD 3.2 (1995)

• RELAP5-3D (1995 to Present)• RELAP5-RT (1997 to Present)

FLASH 1966• 3 volume system• Fill via table• Choke flow model• Secondary side as

constant heat transfer coefficient

• HEM field equations• Plate fuel, heat in only• Explicit numerics

Hot Cold

Przr

RELAPSE-1 RELAP1 1966• Evolved from FLASH (basic leak/fill capability)

– Reactor kinetics– Control systems

• 3 Volumes– Heat Ex to Rx In– Rx Out to Heat Ex– Pressurizer

• Rx Heat added at junction of volume 1 & 2

• Models for nucleate and film boiling

RELAP-2• Similar “look&feel” of RELAPSE

– Same leak/fill capability

– Same heat transfer

– 3 volume system

• New models

– BWR considerations

– Bubble separation

– Introduced steam tables

• Other– 2x faster than RELAPSE

– Improved stability

– Ported to other platforms

RELAP2 BWR Description

RELAP3 1970

• Evolved from RELAPSE and RELAP2– 20 volumes– BWR applications– Trip logic– Valves– Fill/leak pressure

dependent– Fuel pins/plates;

conduction model– Expanded heat

transfer models

RELAP4 1973

• Evolved from RELAP3– 100 Volumes– True 1-D– 2-fluid, slip– N2 field for accum– Secondary Network– Momentum flux term

(dP/dA) & form losses– Reflood HT, fuel gap

and metal-water Rx– Implicit numerics

RELAP5 1979• Evolved from RELAP4

– “1000” volumes– 1-D and X-flow– 2-fluid, nonHEM– More Trips/Controls– Interfacial Momentum – Multi-channel/fuel rod

model– Much expanded

models & correlations– Semi-Implicit numerics

RELAP5-3D 1995

• Evolved from RELAP5– Multi-dimensional

hydraulics and Rx kinetics– Models for Radiation HT &

conduction enclosure– Fuel/cladding deformation– New fluids (Gen IV Rx)– Code coupling– BPLU numeric solver– FORTRAN 90/95

RELAP has a Constant History of Added Capability

• As new versions of RELAP are developed, capability is greatly increased at the expense of complexity and the need for better computer resources

• RELAP 1,2,3 – 3 Equations – mass, energy, and momentum– Designed for LBLOCA analysis

• RELAP4– 3 Equations – mass, energy, and momentum– LBLOCA– SBLOCA

RELAP has a Constant History of Added Capability (cont.)

• RELAP5 MOD 0,1, 1.5– 5 Equations - two mass, one energy, and two momentum– LBLOCA– SBLOCA– Semi implicit numerics– Operational transients

• RELAP5 MOD 2, 2.5, 3.0, 3.1, 3.2– 6 Equations - two mass, two energy, and two momentum

• Semi, Nearly implicit numerics• Crossflow model• CCFL Model• Metal water reactions• Level tracking model

RELAP5 Developers

RELAP5-3D ModelingCapability

• Single or two-phase flow• 1-, 2-, or 3- dimensional flow networks• Reactor kinetics – 1-, 2-, or 3-dimensional nodal kinetics model• Heat Transfer – conduction, convection, radiation• Components – pump, compressor, turbine, valves, phase-

separators, accumulators, jet-mixers, and pressurizers• Process models – critical flow, abrupt area change, form loss,

phase separation at tees• Coupling capability to other codes such as CFD through the

PVM Executive • Control systems• Graphical user interface

Major Features of RELAP5-3D• 6 equations

• Semi implicit hydrodynamics

• Nearly implicit hydrodynamics• Single or two-phase flow• 1-, 2-, or 3- dimensional flow networks• Reactor kinetics – 1-, 2-, or 3-dimensional nodal kinetics model• Heat Transfer – conduction, convection, radiation

• Cross Flow model

• Ability to couple directly to other codes through PVM and the PVM Executive

• Metal-water interaction model

• 3D hydro

• 3D kinetics

• Additional fluids

• BPLU solver

• Simulator capability

• ECC and ECC mixing models

• Godunov 2nd order in space boron tracking model

• Plant and piping components, trips, controls

Major Features of RELAP5-3D (cont.)

• RELAP5 GUI and ability to link to other GUIs such as SNAP• GEN IV heat transfer models• Pressurizer spray model• Feedwater heater model• Radiological model transport• 2-D conduction• Alternate heat conduction to fluids• Compressor model• Gas diffusion model

26 TOTAL RELAP5-3D Working Fluids

• Water (H2O)• 1984 light water (H2ON)• Heavy Water (D2O)• Hydrogen• Lithium• Potassium• Helium• Nitrogen• Sodium• Sodium-Potassium (NaK)• Lithium-Lead• Ammonia• Glycerol• Bismuth-Lead

• 1995 light water (H2O95)• Carbon Dioxide• New Helium (HeN)• New Xenon (XeN)• New Helium-New Xenon

(HeNXeN)• Molten Salt 1 (LiF-BeF2 (FLiBe))• Molten Salt 2 (NaBF4-NaF)• Molten Salt 3 (LiF-NaF-KF

(FLiNaK))• Molten Salt 4 (NaF-ZrF4)• DowThermA• R134A• Super Critical water• Blood

Different fluids can exist in thermally-coupled loops

Noncondensable Gases in RELAP5-3D

• Air• Argon• Helium• Hydrogen• Nitrogen• Xenon• Krypton, SF• Oxygen• CO2 • CO

The Graphical User Interface (2.4.2)Facilitates Analysis of Calculated

Results• Graphical

display generated from input data

• Color scale displays user-selected parameter

• Point & click plots

• Replay capability at any speed

VERSIONS OF RELAP5-3D

• RELAP5-3D Version 2.4.3 (Current Released version)• RELAP5-RT Version 2.4.2• RELAP5-3D Version 3.0.0 Beta (Available to current

license holders)• RELAP5-3D Version 3.1.0 (Release date TBD)

RELAP5-3D Key CHANGES SINCE VERSION 2.4.3

• FORTRAN 95• Restructuring with FOR_STRUCT • Developmental Assessment • Improved Nodal Kinetics • ANS 2005 Decay Heat Standard • Improved Time Step Control• Accuracy Based Thermodynamic Properties

RELAP5-3D Key CHANGES SINCE VERSION 2.4.2 (Cont)

• Institutionalized Card 1, Option 3 (Consistent Sound Speed Calculation between Volumes and Junctions when Noncondensables are Present) 

• Added Card 1 Option 27 to set Theta Velocity in Outermost Ring of Rigid Body Rotation and R-theta Symmetric Problems to 1.0 m/s

• Added Card 1 Option 29 to allow more Accurate Solution to Momentum Equations for Low Flows 

• Allow Fluid Interactive Capability for the Working Fluid D2O • Allow Input Options NEW and NEWATH to use all Working Fluids • Added Command Line Argument ‘-stat’ for Run Statistics for

Developmental Assessment• 2D Heat Conduction Model without Reflood• Alternate Heat Structure – Fluid Coupling Model• Linux SuSe Platform Capability

RELAP5-3D Key CHANGES SINCE VERSION 2.4.3 (Cont.)

• Pump Head and Torque Multiplier as a Function of Pressure and Void Fraction

• CO2 Properties Improvement for Running near and through the Critical Point

• Improved Compressor Model (Allow Input Negative Flows on Speed Tables, Allow Compressors to Run with Noncondensable Gases) 

• Allow Efficiency Multiplier (for Type-3 Turbine) using a Control Variable and Turbine Inlet Junction Form Loss Multiplier using a Control Variable

• Allow PVM Coupled Restart from Uncoupled Runs • Modified PVM Coupling to send any RELAP5-3D Nodal Kinetics

Variable instead of the Restricted List of Power, Zone, Heat Structure Average Temperature, etc.

RELAP5-3D Applications

• Wide range of nuclear power reactor applications• Many non-nuclear and non nuclear applications• Capability to analyze any type of flow and heat

transfer phenomena in a piping network

Applications of RELAP5-3D

• Naval Reactors• LWR Safety Analysis• AP-600• Nuclear power plant training simulators• Licensing code development for INER and MHI• Advanced Test Reactor• DOE International Nuclear safety Program• Cryogenic storage and delivery systems• SP-100 nuclear system• Municipal steam delivery systems• Sodium fast reactors• Wide Range of university applications

Advanced Reactor Applications

• Super Critical Water Reactor• Gas Fast Reactor• Molten Salt• Liquid Metal• NGNP

GEN IV Advanced Reactor Design Applications

• NGNP high temperature gas reactor • High Temperature Test Facility• Super critical water reactor• Gas fast reactor• Molten salt• Pb-Bi

NGNP Advanced Reactor Applications

• The foundation for a thermal-hydraulic systems analysis capability directed specifically toward the NGNP has been under development for several years at the INEEL.

• While the basic physical models in RELAP5-3D have been extensively validated for light water reactors, its applicability to the NGNP design must be demonstrated.

• A program encompassing validation, experiments, and further code development will accomplish this. High Temperature Test facility and MHTGR calculations

• RELAP5-3D provides a system-wide analysis capability and FLUENT or STARR CCM+ provides the CFD capability.

• In-vessel and ex-vessel studies

Core

UpperPlenum

LowerPlenum

BalanceOfPlant

CFD model

RELAP5-3Dmodel

RELAP5-3D Coupled to STAR CCM+ and FLUENT For Detailed Analysis

GT MHTGR Fluent Calculation

RELAP5-3D Licenses and IRUG

• RELAP5-3D is copyrighted by BEA• Growing membership in IRUG • Multiyear commercial and university license agreements being

executed• BEA continue to improved turn around time for new license requests

– 138 days in FY’09 compared to 32 days first quarter FY’11– state universities accepting alternative language for venue and

applicable law• Information about RELAP5 and the International RELAP5 Users

Group can be found at www.inel.gov/relap5/

Current License Structure

• License Costs – Depends on type of code desired, source or

executable– Level of support needed for technical assistance

Future RELAP Development

• Advanced code development is currently underway• Starting a long term project to add uncertainty

quantification to RELAP5-3D• RELAP6 (Presentation later)• RELAP7 (Presentation later)

Acknowledgements

• Bob Martin for material on the early codes and their capability