Modeling of Kerena Emergency Condenser

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KERENA is an innovative boiling water reactor concept equipped with several passive safety systems. For the experimental verification of performance of the systems and for codes validation, the Integral Test Stand Karlstein (INKA) was built in Karlstein, Germany. The emergency condenser (EC) system transfers heat from the reactor pressure vessel (RPV) to the core flooding pool in case of water level decrease in the RPV. EC is composed of a large number of slightly inclined tubes. During accident conditions, steam enters into the tubes and condenses due to the contact of the tubes with cold water at the secondary side. The condensed water flows then back to the RPV due to gravity. In this paper two approaches for modeling of condensation in slightly inclined tubes are compared and verified against experiments. The first approach is based on the flow regime map. Depending on the regime, heat transfer coefficient is calculated according to specific semi-empirical correlation. The second approach uses a general, fully-empirical correlation. The models are developed with utilization of the object-oriented Modelica language and the open-source OpenModelica environment. The results are compared with data obtained during a large scale integral test, simulating loss of coolant accident performed at Integral Test Stand Karlstein (INKA). The comparison shows a good agreement.Due to the modularity of models, both of them may be used in the future in systems incorporating condensation in horizontal or slightly inclined tubes. Depending on his preferences, the modeller may choose one-equation based approach or more sophisticated model composed of several exchangeable semi-empirical correlations.

[1] IAEA, Power Reactor Information System,

[2] Drescher R., Wagner T. and Leyer S.: Passive BWR integral LOCA testing at Karlstein test facility INKA. VGB PowerTech, 5 (2014), 33-37.

[3] Modelica website

[4] OpenModelica website

[5] Schaffrath A., Hicken E.F., Jaegers H. and Prasser H-M.: Operation conditions of the emergency condenser of the SWR1000. Nucl. Eng. Des. 188(1999), 3, 303-318.

[6] Schaffrath A., Krüssenberg A., Fjodorow A., Gocht U., Lischke W.: Modeling of condensation in horizontal tubes. Nucl. Eng. Des. 204(2001), 1-3, 251-265.

[7] VDI Heat Atlas, Second Edition. Springer-Verlag Berlin Heidelberg 2010.

[8] Nusselt W.: Oberflächenkondensation des Wasserdampfes. Zeitschr. Vereins Deutsher Ingenieure 27(1916), 541-546, 569-575.

[9] Tandon T.N., Varma H.K., Grupta C.P.: A new flow regimes map for condensation inside horizontal tubes. J. Heat Transfer 104(1982), 4, 763-768.

[10] Soliman E.N.: The mist-annular transition during condensation and its influence on the heat transfer mechanism. Int. J. Mutiphas. Flow 12(1986), 2, 277-288.

[11] Grimley S.S.: Liquid flow conditions in packed towers. Trans. Inst. Chem. Eng. 23(1945), 228-235.

[12] Kutateladse S.S.: Fundamentals of Heat Transfer. Edward Arnold, 1963.

[13] Kosky P.G., Staub W.F.: Local condensing heat transfer coefficient in the annular flow regime. AICHE J. 17(1971), 5, 1037-1043.

[14] Jaster H., Kosky P.G.: Condensation heat transfer in a mixed flow regime. Int. J. Heat Mass Tran. 19(1976), 1, 95-99.

[15] Breber G.W., Palen J.W., Taborek J.: Prediction of horizontal tubeside condensation of pure components. Trans. ASME J. Heat Transfer 102(1980), 3, 471-476.

[16] Sieder E.N., Tate G.E.: Heat transfer and pressure drop of liquids in tubes. Ind. Eng. Chem. 28(1936), 12, 1429-1435.

[17] Shah M.M.: A general correlation for heat transfer during film condensation inside pipes. Int. J. Heat Mass Tran. 22(1979), 4, 547-556.

[18] Bergles A.E.: The determination of forced-convection surface boiling heat transfer. J. Heat Transfer 86(1964) 3, 365-372.

[19] Churchill W., Chu H.H.S.: Correlation equations for laminar and turbulent free convection from a horizontal cylinder. Int. J. Heat Mass Tran. 18(1975), 1049-1053.

[20] Mikielewicz D., Andrzejczyk R.: Comparative study of flow condensation in conventional and small diameter tubes. Arch. Thermodyn. 33(2012), 2, 67-83 DOI: 10.2478/v10173-012-0011-2

Archives of Thermodynamics

The Journal of Committee on Thermodynamics and Combustion of Polish Academy of Sciences

Journal Information

CiteScore 2016: 0.54

SCImago Journal Rank (SJR) 2016: 0.319
Source Normalized Impact per Paper (SNIP) 2016: 0.598


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