DOI QR코드

DOI QR Code

Development of a drift-flux model based core thermal-hydraulics code for efficient high-fidelity multiphysics calculation

  • Received : 2019.02.19
  • Accepted : 2019.04.02
  • Published : 2019.09.25

Abstract

The methods and performance of a pin-level nuclear reactor core thermal-hydraulics (T/H) code ESCOT employing the drift-flux model are presented. This code aims at providing an accurate yet fast core thermal-hydraulics solution capability to high-fidelity multiphysics core analysis systems targeting massively parallel computing platforms. The four equation drift-flux model is adopted for two-phase calculations, and numerical solutions are obtained by applying the Finite Volume Method (FVM) and the Semi-Implicit Method for Pressure-Linked Equation (SIMPLE)-like algorithm in a staggered grid system. Constitutive models involving turbulent mixing, pressure drop, and vapor generation are employed to simulate key phenomena in subchannel-scale analyses. ESCOT is parallelized by a domain decomposition scheme that involves both radial and axial decomposition to enable highly parallelized execution. The ESCOT solutions are validated through the applications to various experiments which include CNEN $4{\times}4$, Weiss et al. two assemblies, PNNL $2{\times}6$, RPI $2{\times}2$ air-water, and PSBT covering single/two-phase and unheated/heated conditions. The parameters of interest for validation include various flow characteristics such as turbulent mixing, spacer grid pressure drop, cross-flow, reverse flow, buoyancy effect, void drift, and bubble generation. For all the validation tests, ESCOT shows good agreements with measured data in the extent comparable to those of other subchannel-scale codes: COBRA-TF, MATRA and/or CUPID. The execution performance is examined with a mini-sized whole core consisting of 89 fuel assemblies and for an OPR1000 core. It turns out that it is about 1.5 times faster than a subchannel code based on the two-fluid three field model and the axial domain decomposition scheme works as well as the radial one yielding a steady-state solution for the OPR1000 core within 30 s with 104 processors.

Keywords

Acknowledgement

Supported by : Korea Atomic Energy Research Institute (KAERI), Korea Hydro and Nuclear Power Central Research Institute (KHNP CRI)

References

  1. B. Kochunas, et al., VERA core simulator methodology for pressurized water reactor cycle depletion, Nucl. Sci. Eng. 185 (2017).
  2. M. Christienne, et al., Coupled TORT-TD/CTF capability for high-fidelity LWR core calculations, in: PHYSOR 2010, 2010. Pittsburgh, PA, USA.
  3. J. Lee, et al., nTRACER/COBRA-TF coupling and initial assessment, in: Proc. Of the KNS 2015, Spring, Jeju, Rep. of Korea, 2015.
  4. J.A. Turner, et al., The virtual environment for reactor applications (VERA). Design architecture, J. Comput. Phys. 326 (2016) 544-568.
  5. V. Seker, et al., Reactor simulation with coupled Monte Carlo and computational fluid Dynamics, in: Joint International Topical Meeting on Mathematics & Computation and Supercomputing in Nuclear Applications (M&C + SNA 2007), 2007. Monterey, California, USA.
  6. R. Tuominen, et al., Coupling SERPENT and OPENFAOM for neutronics-CFD multi-physics calculations, in: Proc. Of PHYSOR, 2016. Sun Valley, ID, USA, 2016.
  7. R. Salko, M. Avramova, COBRA-TF Subchannel Thermal-Hydraulics Code (CTF) Theory Manual-Revision 0, The Pennsylvania State University, 2015.
  8. S. Patankar, Numerical Heat Transfer and Fluid Flow, CRC press, 1980.
  9. MPACT TEAM, Consortium for Advanced Simulation of Light Water Reactors, 2015. MPACT Theory Manual v2. 1.0.
  10. A. Seubert, K. Velkov, S. Langenbuch, The time-dependent 3D discrete ordinates code TORT-TD with thermal-hydraulic feedback by ATHLET models, in: PHYSOR 2008, Interlaken, Switzerland, 2008.
  11. Y.S. Jung, et al., Practical numerical reactor employing direct whole core neutron transport and subchannel thermal/hydraulic solvers, Ann. Nucl. Energy 62 (2013) 357-374. https://doi.org/10.1016/j.anucene.2013.06.031
  12. H.Y. Yoon, et al., CUPID Code Manual Volume I: Mathematical Models and Solution Methods, Korea Atomic Energy Research Institute, 2011.
  13. S.J. Yoon, et al., Application of CUPID for subchannel-scale thermal-hydraulic analysis of pressurized water reactor core under single-phase conditions, Nucl. Eng. Technol. 50 (2018) 54-67. https://doi.org/10.1016/j.net.2017.09.008
  14. J.R. Lee, H.Y. Yoon, Multi-physics approach for nuclear reactor analysis using thermal-hydraulics and neutron kinetics coupling methodology, in: Tenth International Conference on Computational Fluid Dynamics, 2018. Barcelona, Spain.
  15. H. Kwon, et al., Validation of a Subchannel Analysis Code MATRA Version 1.1, Korea Atomic Energy Research Institute, 2014. KAERI/TR-5581/2014.
  16. S. Kim, et al., Preliminary coupling of MATRA code for multi-physics analysis, in: Proc. Of the KNS 2014 Spring Meeting, Jeju, Rep. of Korea, 2014.
  17. C.B. Shim, et al., Cross flow modeling in direct whole core transport calculation with a subchannel solver, in: Proc. ICAPP 2013, Jeju, Rep. of Korea, 2013.
  18. N. Zuber, J. Findlay, Average volumetric concentration in two-phase flow systems, J. Heat Transf. 87 (4) (1965) 453-468. https://doi.org/10.1115/1.3689137
  19. M. P. Paulsen et al., "RETRAN-3DdA Program for Transient Thermal-Hydraulic Analysis of Complex Fluid Flow Systems Volume vol 3: User's Manual," NP-7450.
  20. Y.J. Chung, et al., Development and assessment of system analysis code, TASS/ SMR for integral reactor, SMART, Nucl. Eng. Des. 244 (2012) 52-60. https://doi.org/10.1016/j.nucengdes.2011.12.013
  21. L. Wolf, L.J.M. Guillebaud, A. Faya, WOSUB: a Subchannel Code for Steady- State and Transient Thermal-Hydraulic Analysis of BWR Fuel Pin Bundles, Energy Laboratory, Massachusetts Institute of Technology, 1978.
  22. M.B. Carver, et al., Simulation of the distribution of flow and phases in vertical and horizontal bundles using the ASSERT-4 subchannel code, Nucl. Eng. Des. 122 (1990) 413-424. https://doi.org/10.1016/0029-5493(90)90224-L
  23. B. Chexal, et al., A void fraction correlation for generalized applications, Prog. Nucl. Energy 27 (4) (1992) 255-295. https://doi.org/10.1016/0149-1970(92)90007-P
  24. N.E. Todreas, M.S. Kazimi, Nuclear Systems Volume I: Thermal Hydraulic Fundamentals, CRC press, 2011.
  25. A.A. Armand, The Resistance during the Movement of a Two-phase System in Horizontal Pipes, Izvestiia Vsesoiuznyi Teplotekhnicheskii Institut, 1946.
  26. J.E. Kelly, S.P. Kao, M.S. Kazimi, THERMIT-2: A Two-Fluid Model for Light Water Reactor Subchannel Transient Analysis, MIT Energy Laboratory Electric Utility Program, 1981. MIT-EL-81-014.
  27. S.G. Beus, Two-Phase Turbulent Mixing Model for Flow in Rod Bundles, Bettis Atomic Power Lab., Pittsburgh, 1972. No. WAPD-T-2438.
  28. T. R.-3. C. D. Team, RELAP5-3D Code Manual Volume IV: Models and Correlations, Idaho National Engineering and Environmental Laboratory, 2002. INEEL-EXT-98-00834.
  29. R.T. Lahey, A mechanistic subcooled boiling model, in: Proc. Of the 6th Int. Heat Transfer Conference, 1978.
  30. J.P. Van Doormaal, G.D. Raithby, Enhancement of the SIMPLE method for predicting incompressible fluid flows, Numer. Heat Tran. 7 (2) (1984) 147-163.
  31. M. Mohitpour, G. Jahanfarnia, M. Shams, An advancement in iterative solution schemes for three-dimensional, two-fluid modeling of two-phase flow in PWR fuel bundles, Ann. Nucl. Energy 63 (2014) 83-99. https://doi.org/10.1016/j.anucene.2013.07.007
  32. PETSc Team, PETSc Users Manual, Argonne National Laboratory, 2018. ANL-95/11 - Rev. 3.10.
  33. R.K. Salko, R.C. Schmidt, M.N. Avramova, Optimization and parallelization of the thermalehydraulic subchannel code CTF for high-fidelity multi-physics applications, Ann. Nucl. Energy 84 (2015) 122-130. https://doi.org/10.1016/j.anucene.2014.11.005
  34. R. Salko, et al., CTF Validation, CASL, 2016. CASL-U-2016-1113-000.
  35. V. Marinelli, L. Pastori, B. Kjellen, Experimental Investigation of Mass Velocity Distribution and Velocity Profiles in an LWR Rod Bundle, American Nuclear Society, Rome, Italy, 1972. Trans.
  36. E. Weiss, R.A. Markley, A. Battacharyya, Open duct cooling-concept for the radial blanket region of a Fast Breeder reactor, Nucl. Eng. Des. 16 (4) (1971) 375-386. https://doi.org/10.1016/0029-5493(71)90001-X
  37. J.M. Bates, E.U. Khan, Investigation of combined free and forced convection in a 2x6 rod bundle during controlled flow transients, PNL- 3135 (1980).
  38. R.W. Sterner, R.T. Lahey Jr., Air/water Subchannel Measurements of the Equilibrium Quality and Mass-Flux Distribution in a Rod bundle.[BWR], Rensselaer Polytechnic Inst., 1983. No. NUREG/CR-3373.
  39. A. Rubin, et al., OECD/NRC Benchmark Based on NUPEC PWR Subchannel and Bundle Tests (PSBT), Volume I: Experimental Database and Final Problem Specifications, Nuclear Energy Agency, 2010. US NRC OECD.
  40. H.Y. Yoon, J.J. Jeong, A continuity-based semi-implicit scheme for transient two-phase flows, J. Nucl. Sci. Technol. 47 (9) (2010) 779-789. https://doi.org/10.1080/18811248.2010.9711654