Theoretical studies on thermal stratification in a side heated cavity
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N. V. Satish Kumar
Abstract
The Advanced Heavy Water Reactor (AHWR) being designed in India is a vertical pressure tube type boiling water-cooled and heavy water moderated reactor. A key feature of the AHWR is the use of simple passive systems to respond to any postulated accidental condition. Passive Containment Cooling System (PCCS), is one such system, which provides long term cooling for the reactor containment following a Loss Of Coolant Accident (LOCA). The system consists of Immersed Condensers immersed in a gravity driven water pool. One of the important phenomena related to PCCS functioning is the effect of thermal stratification in the water pool. The heat transfer from IC to water pool takes place by natural convection. In this process, the pool water can get stratified. Towards the top of the water pool, the temperature of water may reach almost the boiling point while at the bottom of the pool, the water is likely to remain at the initial temperature. Hence, in order to study the integral system response of PCCS, the phenomenon of stratification requires to be investigated. Towards this objective, the case of a rectangular enclosure heated symmetrically on both the vertical sides was considered and a two-dimensional analysis was done by numerically solving the mass, momentum and energy equations. Theoretical results were generated by the use of a computer code developed for this purpose and the results are then compared with the experimental results available in literature.
Kurzfassung
Der in Indien entwickelte fortgeschrittene Schwerwasserreaktor (AHWR) ist ein vertikaler Druckröhrensiedewasserreaktor mit Schwerwasser als Moderator und Kühlmittel. Ein wesentliches Merkmal des AHWR ist die Auslegung mit einfachen passiven Sicherheitssystemen für alle postulierten Störfallverläufe. Ein solches System ist das passive Kühlsystem des Sicherheitsbehälters (PCCS), das eine Langzeitkühlung des Reaktorsicherheitsbehälters bei einem Kühlmittelverluststörfall (LOCA) gewährleistet. Das System besteht aus Kondensatoren (IC) innerhalb eines Wasserbeckens nach dem Schwerkraftprinzip. Der Wärmetransfer vom IC zum Wasserbecken erfolgt durch natürliche Konvektion. Während dieses Prozesses kann im Wasserbecken eine Wärmeschichtung entstehen. Oben im Becken kann die Temperatur des Wassers nahezu den Siedepunkt erreichen, während am Boden des Beckens das Wasser nahezu seine Anfangstemperatur behält. Zur Untersuchung der integralen Lösung des PCCS muss deshalb das Phänomen der Wärmeschichtung näher betrachtet werden. Dazu wurde am Beispiel eines rechteckigen Behälters, der an den vertikalen Seiten symmetrisch erwärmt wurde, eine zweidimensionale numerische Analyse der entsprechenden Massen-, Impuls und Energiegleichungen durchgeführt. Zu diesem Zweck wurde ein Computercode entwickelt und die berechneten Ergebnisse wurden mit den in der Literatur vorhandenen experimentellen Ergebnissen verglichen.
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© 2005, Carl Hanser Verlag, München
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Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries/Kurzfassungen
- Editorial
- 70 Volumes Kerntechnik
- Technical Contributions/Fachbeiträge
- Uncertainty and sensitivity analysis of void and power reactivity coefficients in an RBMK-1500 reactor core
- Theoretical studies on thermal stratification in a side heated cavity
- Measurement of the neutron fluence on the spallation source at Dubna
- Neutron reflection and leakage models for one-dimensional reactor computations
- Reactivity worth of the control rods at the ET-RR-2 reactor core
- Neutronic conceptual design of the ETRR-2 cold neutron source
- Criticality analyses of regions containing uranium in the earth history
- Semi-statistical mechanical fuel rod design
- Brennstabauslegung und Brennstabmodellierung – Teil 2
- The chemical separation of Eka-Hg from CERN W targets in view of recent relativistic calculations
- Letter to the Editor
- Comments on the question of the discovery of element 112 as early as 1971
