Table Of ContentIAEA-TECDOC-1520
Theoretical and Experimental
Studies of Heavy Liquid Metal
Thermal Hydraulics
Proceedings of a technical meeting
held in Karlsruhe, Germany, 28–31 October 2003
October 2006
IAEA-TECDOC-1520
Theoretical and Experimental
Studies of Heavy Liquid Metal
Thermal Hydraulics
Proceedings of a technical meeting
held in Karlsruhe, Germany, 28–31 October 2003
October 2006
The originating Section of this publication in the IAEA was:
Radiation and Transport Safety Section
International Atomic Energy Agency
Wagramer Strasse 5
P.O. Box 100
A-1400 Vienna, Austria
THEORETICAL AND EXPERIMENTAL STUDIES OF
HEAVY LIQUID METAL THERMAL HYDRAULICS
IAEA, VIENNA, 2006
IAEA-TECDOC-1520
ISBN 92–0–111806–6
ISSN 1011–4289
© IAEA, 2006
Printed by the IAEA in Austria
October 2006
FOREWORD
Through the Nuclear Energy Department’s Technical Working Group on Fast Reactors
(TWG-FR), the IAEA provides a forum for exchange of information on national programmes,
collaborative assessments, knowledge preservation, and cooperative research in areas agreed
by the Member States with fast reactor and partitioning and transmutation development
programmes (e.g. accelerator driven systems (ADS)). Trends in advanced fast reactor and
ADS designs and technology development are periodically summarized in status reports,
symposia, and seminar proceedings prepared by the IAEA to provide all interested IAEA
Member States with balanced and objective information.
The use of heavy liquid metals (HLM) is rapidly diffusing in different research and industrial
fields. The detailed knowledge of the basic thermal hydraulics phenomena associated with
their use is a necessary step for the development of the numerical codes to be used in the
engineering design of HLM components. This is particularly true in the case of lead or
lead-bismuth eutectic alloy cooled fast reactors, high power particle beam targets and in the
case of the cooling of accelerator driven sub-critical cores where the use of computational
fluid dynamic (CFD) design codes is mandatory.
Periodic information exchange within the frame of the TWG-FR has lead to the conclusion
that the experience in HLM thermal fluid dynamics with regard to both the
theoretical/numerical and experimental fields was limited and somehow dispersed. This is the
case, e.g. when considering turbulent exchange phenomena, free-surface problems, and
two-phase flows. Consequently, Member States representatives participating in the
35th Annual Meeting of the TWG-FR (Karlsruhe, Germany, 22–26 April 2002)
recommended holding a technical meeting (TM) on Theoretical and Experimental Studies of
Heavy Liquid Metal Thermal Hydraulics.
Following this recommendation, the IAEA has convened the Technical Meeting on
Theoretical and Experimental Studies of Heavy Liquid Metal Thermal Hydraulics (28–
31 October 2003). The TM was hosted by the Forschungszentrum Karlsruhe, Germany.
The scope of the TM was to provide a global forum for information exchange on the most
recent theoretical and experimental studies of HLM thermal hydraulics.
The main objective of the TM was to assess the shortcomings of the present CFD codes used
for HLM simulation and to identify future research needs, in both the numerical and
experimental area.
The IAEA would like to express its appreciation to all the participants, authors of papers,
chairpersons, and to the hosts at Forschungszentrum Karlsruhe.
The IAEA officer responsible for this publication was A. Stanculescu of the Division of
Nuclear Power.
EDITORIAL NOTE
The papers in these proceedings are reproduced as submitted by the authors and have not undergone
rigorous editorial review by the IAEA.
The views expressed do not necessarily reflect those of the IAEA, the governments of the nominating
Member States or the nominating organizations.
The use of particular designations of countries or territories does not imply any judgement by the
publisher, the IAEA, as to the legal status of such countries or territories, of their authorities and
institutions or of the delimitation of their boundaries.
The mention of names of specific companies or products (whether or not indicated as registered) does
not imply any intention to infringe proprietary rights, nor should it be construed as an endorsement
or recommendation on the part of the IAEA.
The authors are responsible for having obtained the necessary permission for the IAEA to reproduce,
translate or use material from sources already protected by copyrights.
CONTENTS
SUMMARY...............................................................................................................................1
SESSION 1: REVIEW OF THE STATE OF ART OF PRESENT CDF CODES
Turbulence modeling issues in ADS thermal and hydraulic analyses.......................................9
G. Groetzbach
Two CFD applications to the design of the active zone of HLM
spallation targets...................................................................................................................33
P. Roubin
CFD analysis of the thermal-hydraulic performance of the ESS target...................................49
E.M.J. Komen, F. Roelofs, J. Wolters, G. Hansen
Validation of CFD models with respect to the thermal-hydraulic design
of the ESS target...................................................................................................................59
J. Wolters, G. Hansen, E.M.J. Komen, F. Roelofs
CFD analysis of the heavy liquid metal flow field in the MYRRHA pool..............................77
E.M.J. Komen, P. Kupschus, K. Van Tichelen, H. Aït Abderrahim, F. Roelofs
Comparative analysis of the benchmark activity results on the ADS
target model..........................................................................................................................89
A. Sorokin, G. Bogoslovskaia, V. Mikhin, S. Marzinuk
Free surface fluid dynamics code adaptation by experimental evidence
for the MYRRHA spallation target....................................................................................101
K. Van Tichelen, P. Kupschus, M. Dierckx, H. Aït Abderrahim, F. Roelofs
Thermohydraulic behaviour in an ADS target model............................................................111
A. Peña, G.A. Esteban, J. Sancho
Development and application of CFD codes MASKA-LM and PORT 3D for
investigation of thermal hydraulics of lead cooled fast reactor BREST............................119
A.A. Veremeev, V.Ya. Kumayev, A.A. Lebezov
CFD simulation of X-ADS downcomer thermal stratification..............................................135
V. Anissimov, A. Alemberti
Experiences from using the STAR-CD code for Pb-Bi-coolant flows..................................151
J. Carlsson, H. Wider
CFD simulation of SINQ HETSS mercury experiments.......................................................165
T.V. Dury
SESSION 2: REVIEW OF CURRENT AND PLANNED EXPERIMENTAL
HLM PROGRAMS
Thermal hydraulic research and development needs for lead fast reactors............................195
J.J. Sienicki, D.C. Wade, C.P. Tzanos
Thermohydraulic research for the core of the BREST reactor...............................................213
A.V. Zhukov, A.D. Efanov, A.P. Sorokin, J.A. Kuzina,
V.P. Smirnov, A.I. Filin, A.G. Sila-Novitsky, V.N. Leonov
Pre-test analysis of the MEGAPIE integral test with RELAP5.............................................227
W.H. Leung, B. Sigg
Experimental determination of the local heat transfer coefficient for
MEGAPIE target window using infrared thermography...................................................243
J.A. Patorski, F. Gröschel, I. Platnieks
Thermal-hydraulic ADS lead bismuth loop (tall) and experiments
on a heat exchanger............................................................................................................259
B.R. Sehgal, W.M. Ma, A. Karbojian
HELIOS for thermal-hydraulic behaviour of Pb-Bi cooled fast reactor peacer.....................271
I.S. Lee, K.Y. Suh
Void-fraction measurements in two-phase nitrogen-mercury flows......................................295
P. Satyamurthy, N.S. Dixit, P. Munshi
SESSION 3: ELABORATION OF FUTURE ACTIVITIES
Studies on heavy liquid metal thermal-hydraulics:
Existing test facilities and test programs............................................................................307
J.U. Knebel, C. Fazio
LIST OF PARTICIPANTS....................................................................................................315
SUMMARY
1. INTRODUCTION
The use of heavy liquid metals (HLM) is rapidly diffusing in different research and industrial
fields. The detailed knowledge of the basic thermal hydraulics phenomena associated with
their use is a necessary step for the development of the numerical codes to be used in the
R&D as well as in the engineering design of HLM components. This is particularly true in the
case of high power particle beam targets and in the case of the cooling of accelerator driven
sub-critical cores where the use of computational fluid dynamic (CFD) design codes is
mandatory.
The scope of the topical Technical Meeting on Theoretical and Experimental Studies of
Heavy Liquid Metal Thermal Hydraulics was to provide a global forum for information
exchange on the most recent theoretical and experimental studies of HLM thermal hydraulics.
The main objective of the technical meeting was the assessment of the shortcomings of the
present CFD codes used for HLM simulation and to propose future research activities, in both
the numerical and experimental area.
More specifically, the technical meeting:
(i) Reviewed the state of the art of present CFD codes by:
— Assessing their degree of precision and accuracy;
— Identifying open issues in current turbulence models;
— Identifying open issues in free surface phenomena and two-phase flows;
— Addressing development needs of adequate physical models for HLM flows;
— Addressing code validation issues.
(ii) Reviewed the current and planned experimental HLM programmes:
— Description of capabilities of existing and planned HLM facilities and work
programme;
— Instrumentation and measurement techniques;
— Description of existing and planned benchmark experiments and databases;
— Thermal hydraulics applications to ongoing projects on spallation targets and
accelerator driven systems (ADS);
— Prospects for international collaboration and coordination of the experimental
activities.
(iii) Elaborated the needs for future activities:
— Definition of numerical and experimental benchmarks (including required
databases);
— International collaboration (networking and coordination among institutions
involved in HLM thermal hydraulics).
(iv) Discussed IAEA’s potential role in meeting Member States’ needs for information
exchange and collaborative R&D in the field of HLM thermal hydraulics.
Twenty-five participants from ten Member States and two international organizations
attended the technical meeting, which heard twenty-three papers.
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2. CONCLUSIONS
In reviewing present CFD codes, the papers addressed the key issues of CFD code
characterization, i.e. modelling, material property data, numerical problems and code
performance, as well as code usability. From the papers presented as well as from the ensuing
in-depth discussions, the main conclusions reached by the technical meeting addressed the
following areas: turbulence phenomena, two-phase and free-surface flows phenomena, as well
as experiments and measurement techniques.
(i) Turbulence
─ HLM fluid dynamic phenomena can often be separated from thermal
phenomena, except where buoyancy is significant.
─ Any investigation on improved modelling of heat transfer needs experimental
data of the complementary flow field, sometimes requiring complementary
experiments with different fluids.
─ In particular, there is a need for high accuracy data for detached and
recirculating flows.
─ Modelling of flows near a wall is understood, but needs to be incorporated in
best practice guidelines.
─ There is a need to categorise flow situations occurring in geometries typical for
ADS and HLM cooled system and identify CFD validation requirements for the
phenomena encountered.
─ Current commercial codes do not include state of the art knowledge of turbulent
heat transfer in liquid metals (LM), or the incorporated physical models are not
sufficiently validated.
─ For ADS and HLM cooled system applications a better realisation of turbulent
transport of scalar quantities (e.g. concentration field) is required.
─ No single turbulence model covers all flow types present in ADS and HLM
cooled systems, and the best model for a given physical system needs to be
determined by suitable experiments.
─ Existing large eddy simulation (LES) models do not appear to be adequate for
analysing problems of ADS and HLM cooled systems.
(ii) Two-phase flow
Two-phase flow problems are encountered and have a significant relevance in the
design of ADS, fast reactors, and spallation targets. The main fields of application of
two-phase flow phenomena are:
─ Enhancement (or inducement) of natural circulation;
─ Mitigation of pressure waves (for pulsed spallation sources);
─ Phenomena related to the rupture of water heat exchanger tubes: bubble
entrainment, pressure waves.
In HLM, the flow regime of interest is bubbly flow.
As far as two-phase flow phenomena are concerned, system codes and CFD codes are
complementary. However, both numerical code categories have shortcomings:
— The correlations used in system codes need development and validation in HLM
flows. In view of this, basic experimental data are needed on the fundamental
global properties governing the correlations, i.e. void fraction, interfacial area
concentration and phase velocities.
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— As regards CFD codes, much effort is needed to enable the correct simulation of
two-phase flows. Here, the description of drag, lift and virtual mass force are of
primary importance. Both basic and technological experiments are needed.
These should give local information on void fraction, bubble velocity, liquid-
phase velocity, and bubble size spectrum as function of the position. Also the
interaction between bubbles needs to be assessed (coalescence and breakup).
(iii) Free-surface flows
Free-surface flow effects are also of primary importance in the design of fast reactors
and ADS. The main fields of application of these phenomena are:
— Design of a free surface configuration for the windowless spallation target;
— Cover gas entrainment into the liquid pool;
— Sloshing of the pool during earthquakes.
Currently, CFD codes are not able to tackle these problems while taking into account
all relevant phenomena. Extensive code development work is necessary to improve the
capabilities of CFD codes with regard to these problems. Experiments are needed to
validate code development work. The experiments should provide:
— Free surface shape and position (incl. large scale motions, droplet formation);
— Velocity and turbulence fields.
(iv) Fundamental benchmark experiments and measurement techniques
Currently, there are two types of experiments being performed and/or planned: single-
effect experiments, on the one hand side, which aim at the description of physical
phenomena that are currently not understood but must be included in available CFD
code systems, and, on the other hand side, technological studies, which could be part
of benchmark exercises, but in reality are mainly dedicated to specific projects (e.g.
HYPER, PDS-XADS, MYRRHA, ETD, MEGAPIE, BREST). The technical meeting
focused on providing the scope for basic benchmark experiments, while trying to take
into consideration as much as possible the generic aspects common to the
technological studies. There are considerable HLM benchmark activities (both
experimental and numerical) co-funded within the framework of EURATOM
(TECLA, ASCHLIM, MEGAPIE-TEST) and the corresponding national programs.
While these activities resulted in important progress being made with regard to both
measurement techniques and the development of new models to be included in the
CFD codes, significant deficits still exist, especially with regard to local quantities, in
models describing single effects, as well as in the measurement techniques applied to
these parameters. Accordingly, the technical meeting identified the following areas to
be addressed through international benchmark exercises:
— Database for the development of advanced physical models describing HLM
flow to be included in currently existing CFD codes;
— Verification of CFD code packages and their models in simple geometries;
— Qualification of local measurement technologies for velocity, temperature,
surface shapes and their fluctuations, as well as of heat flux simulation tools for
nuclear application;
— Component study of technological devices at ADS relevant operating conditions
(steady state, transient, failure scenarios, determination of operational limits);
— Transport correlations for system analysis codes (e.g. Nu-correlations for
RELAP, and ATHLET);
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