AR-1 experimental model and facility preparation for the purpose of experimental investigation of sodium boiling in fuel subassembly mockup for new generation fast reactor safety justification

UDC: 
УДК 621.039.526.034+621.039.546.8:536.26

Issue of journal:

Abstract: 

Sodium coolant boiling in fast reactor core fuel subassemblies is an accidental operating mode of a nuclear power plant (NPP). In case of surge of sodium boiling the reactor core and all NPP technical characteristics must provide stable heat removal from fuel pins surface by means of boiling coolant. Therefore, the design solutions accepted for the reactor core must eliminate any possibilities of cladding melting or core structure damaging and, furthermore, a time reserve should be provided for stabilizing the operational mode.
One of the most vulnerable situations that may lead to coolant boiling in the Liquid metal fast reactor (LMFR) core resulting in a severe accident is an ULOF (Unprotected Loss of Flow) accident implying simultaneous main pumps electric supply failure and emergency shutdown system breakdown.
As part of the program for safety analysis and justification of perspective LMFR, checking some design solutions and obtaining experimental data for computer code verification work is currently underway to prepare sodium boiling experiments at the IPPE. The experiments will be focused on heat exchange analysis inside the fuel subassembly mockup in different sodium boiling regimes. This experimental work is part of the unified calculation-experimental complex developing program which will make possible to accurately determine operation modes for both operating and projected NPP.
The article presents a brief review of the sodium cooled fast reactor accidental operating mode due to coolant boiling in a fuel subassembly channel by the example of ULOF. Also the authors touch upon the issue of experimental investigations required for verification of two-phase liquid metal coolant models included in the COREMELT code. In addition, the article includes some information on preparation of the experimental facility for sodium boiling in fuel a subassembly mockup is provided as well as a description of the experimental data acquisition system

References: 
1. Adamov E.O., Dzhalovyan A.V., Lopatkin A.V. e.a. Konceptual’nye polozheniya strategii razvitiya yadernoj energetiki Rossii v perspektive do 2100 goda [Conceptual Development Strategy of Russian nuclear power in the run up to 2100]. Atomnaya energiya. 2012, vol. 112, no. 6, pp. 319–330.
2. Rachkov V.I. Atomnaya energetika kak vazhnejshij faktor ustojchivogo razvitiya Rossii v XXI v. [Nuclear energy as an important factor for sustainable development of Russia in XXI century]. Energosberezhenie i vodopodgotovka. 2006, no. 6, pp. 2–4.
3. Rachkov V.I., Poplavskij V.M., Tsibulya A.M. e.a. Koncepciya perspektivnogo energobloka s bystrym natrievym reaktorom BN1200 [Concept of prospective of power unit with fast neutron reactor BN1200]. Atomnaya energiya. 2010, vol. 108, no. 4, pp. 201–205.
4. Kikuchi Y., Haga K. Sodium boiling experiments in a 19pin bundle under lossofflow conditions. Nuclear Engineering and Design. 1981, vol. 66, pp. 357–366.
5. Haga K. Lossofflow experiment in a 37pin bundle LMFBR fuel assembly. Nuclear Engineering and Design. 1984, vol. 82, pp. 305318.
6. Yamaguchi K. Flow pattern and dryout under sodium boiling conditions at decay power levels. Nuclear Engineering and Design. 1987, vol. 99, pp. 247–263.
7. Huber F., Kaiser A., Mattes K., Peppler W. Steady state and transient sodium boiling experiments in a 37pin bundle. Nuclear Engineering and Design. 1987, vol. 100, pp. 377–386.
8. Huber F., Peppler W. Boiling and dryout behind local blockages in sodium cooled rod bundles. Nuclear engineering and design. 1984, vol. 82, pp. 341–363.
9. Kaiser A., Peppler W. Flow rundown experiments in a seven pin bundle. Nuclear Engineering and Design. 1977, vol. 43, pp. 273–283.
10. Kaiser A., Huber F. Sodium boiling experiments at low power under natural convection conditions. Nuclear Engineering and Design. 1987, vol. 100, pp. 367–376.
11. Gnadt P.A., Carbajo J.J., Dearing J.F. Sodium boiling experiments in the THORS facility. Nuclear Engineering and Design. 1984, vol. 82, pp. 241–280.
12. Seiler J.M. Studies on sodium boiling phenomena in outofpile rod bundles for various accidental situations in LMFBR: experiments and interpretations. Nuclear Engineering and Design. 1984, vol. 82, pp. 227–239.
13. Gnadt P.A., Carbajo J.J., Dearing J.F Sodium boiling experiments in the THORS facility. Nuclear Engineering and Design. 1984, vol. 82, pp. 241–280.
14. Efanov A.D., Sorokin A.P., Ivanov E.F. e.a. Issledovaniya teploobmena i ustojchivosti kipeniya zhidkometallicheskogo teplonositelya v konture estestvennoj cirkulyacii [Investigation of heat transfer and stability of boiling liquid metal coolant in the circuit of natural circulation]. Teploenergetika. 2003, no. 3, pp. 20–26.
15. Sorokin G.A., Ninokata H., Sorokin A.P., Endo H., Ivanov Eu.F. Numerical Study of Liquid Metal Boiling in the System of Parallel Bundles under Natural Circulation. Journal of Nuclear Science and Technology. 2006, vol. 43, no. 6, pp. 623–634
16. Efanov A.D., Sorokin A.P., Ivanov E.F. e.a. Teploobmen pri kipenii zhidkogo metalla v sisteme kanalov v rezhime estestvennoj cirkulyacii [Heat exchange at boiling of liquid metal in the channels system under natural circulation]. Teploenergetika. 2007, no. 3, pp. 43–51.
17. Volkov A.V., Kuznecov I.A. Usovershenstvovannaya model’ kipeniya natriya dlya analiza avarij v bystrom reaktore [Improved model of boiling sodium for analysis of accidents in fast reactor]. Izvestiya vuzov. Yadernaya energetika. 2006, no. 2, pp. 101–111.
18. Poplavskij V.M., Matveev V.I., Kuznecov I.A. e.a. Issledovanie vliyaniya natrievogo pustotnogo effekta reaktivnosti na tehnikoekonomicheskie harakteristiki i bezopasnost’ perspektivnogo bystrogo reaktora [Investigation of the influence of the sodium void reactivity effect on the technical and economic characteristics and safety of perspective fast reactor]. Atomnaya energiya. 2010, vol. 108, no. 4, pp. 230–236.
19. Hafizov R.R. Ivanov E.F., Privezencev V.V., Sorokin A.P. Voprosy eksperimental’nogo modelirovaniya processa kipeniya natriya v modeli TVS bystrogo reaktora v avarijnyh rezhimah. Tezisy dokladov i soobschenij XIV Minskogo mezhdunarodnogo foruma po teplomassoobmenu. [Issues of experimental simulation of process boiling of sodium in model fuel assembly of fast reactor at emergency modes. Abstracts and messages XIV Minsk International Forum on Heat and Mass Transfer]. Minsk. 2012, vol. 2, ch. 1, pp. 374–375.
20. Seiler J.M., Juhel D., Dufour Ph. Sodium boiling stabilization in a fast breeder subassembly during an unprotected loss of flow accident. Nuclear Engineering and Design. 2010, vol. 240, pp. 3329–3335.

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