Effect of thermal gap conductance for MoO3 ampoules irradiated in a high neutron flux
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A. Abdelhady
Abstract
During the irradiation process of MoO3 powder with in a high neutron flux, energy deposited in the powder must be released to avoid energy accumulation. The temperature increasing in the powder due to energy accumulation may cause powder phase change and under certain conditions the temperature may reach the melting point. An analytical model was developed to study the effect of gap conductance on the temperature distribution in the powder during the irradiation process. The gap conductance model was studied for helium and nitrogen gases at different pressures to obtain the optimum conditions verifying the safety in heat transfer point of view. It was found that the gap conductance is a function of gas pressure. The model provided the optimum conductivity for the gap filled with helium gas at 1 atm pressure.
Kurzfassung
Während der Bestrahlung von MoO3 Pulver in einem hohen Neutronenfluss muss die im Pulver eingelagerte Energie freigesetzt werden, um eine Energieakkumulation zu verhindern. Die im Pulver durch Energieakkumulation anwachsende Temperatur könnte sonst eine Phasenänderung im Pulver hervorrufen und die Temperatur könnte unter bestimmten Bedingungen den Schmelzpunkt erreichen. Ein analytisches Modell wurde entwickelt zur Untersuchung des Einflusses des Wärmedurchgangs im Spalt auf die Temperaturverteilung im Pulver während der Bestrahlung. Das Wärmedurchgangsmodell im Spalt wurde bei verschiedenen Drucken für Helium- und Stickstoffgas untersucht, um die optimalen Bedingungen zur Verifizierung der Sicherheit in Bezug auf den Wärmetransfer zu erhalten. Es stellte sich heraus, dass der Wärmedurchgang im Spalt eine Funktion des Gasdruckes ist. Das Modell liefert die optimale Leitfähigkeit, wenn der Spalt mit Heliumgas bei 1 Atm Druck gefüllt ist.
References
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© 2010, Carl Hanser Verlag, München
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- Summaries/Kurzfassungen
- Technical Contributions/Fachbeiträge
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- Effect of thermal gap conductance for MoO3 ampoules irradiated in a high neutron flux
- U1 approximation to the neutron transport equation and calculation of the asymptotic relaxation length
- Application of the TN method to critical slab problem for one-speed neutrons with forward and backward scattering and efficiency of reflection coefficient
- Technical Notes/Technische Mitteilungen
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Articles in the same Issue
- Contents/Inhalt
- Contents
- Summaries/Kurzfassungen
- Summaries/Kurzfassungen
- Technical Contributions/Fachbeiträge
- Analyses of loads on reactor pressure vessel internals in a pressurized water reactor due to a loss-of-coolant accident considering fluid-structure interaction
- Preliminary evaluation of a radioactive waste repository safety performance by a Monte Carlo simulation-based reliability model
- Determination of effects of burn up and reflector material on the kinetic parameters for open pool reactor using MCNP code
- Analysis of fuel rod behaviour during limiting RIA in RBMK plants
- Reflection on the ductility of irradiated zircaloy-4 fuel rod cladding
- Prediction, analysis and solution of flow inversion phenomenon in a typical MTR reactor with upward core cooling
- Steam drum process dynamics and level control of a pressure tube BWR
- Nuclear data for cyclotron production of 114mIn/114In and 140Nd/140Pr used in gamma camera monitoring, RIT, ERT and PET
- Effect of thermal gap conductance for MoO3 ampoules irradiated in a high neutron flux
- U1 approximation to the neutron transport equation and calculation of the asymptotic relaxation length
- Application of the TN method to critical slab problem for one-speed neutrons with forward and backward scattering and efficiency of reflection coefficient
- Technical Notes/Technische Mitteilungen
- Rapid preparation of Uranium and Thorium alpha sources by electroplating technique
