U1 approximation to the neutron transport equation and calculation of the asymptotic relaxation length
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Abstract
The U1 approximation is used to determine the asymptotic relaxation length (diffusion length) for one-speed neutrons in a homogeneous slab. The method is based on the series expansion of the neutron angular flux in terms of the Chebyshev polynomials of second kind and then calculating the diffusion length by applying the first order approximation to transport equation. Analytic and numerical results are obtained for the diffusion length and compared with the ones obtained from the method of separation of variables and simple diffusion theory (P1 approximation).
Kurzfassung
Die U1 Approximation wird verwendet zur Bestimmung der asymptotischen Relaxationslänge (Diffusionslänge) bei Ein-Gruppen-Neutronen in einer homogenen Platte. Die Methode basiert auf der Reihenentwicklung des Neutronenflusses in Form von Tschebyscheff Polynomen zweiter Art und anschließender Berechnung der Diffusionslänge durch Anwendung der Approximation erster Ordnung zur Lösung der Transportgleichung. Analytische und numerische Ergebnisse für die Diffusionslänge werden verglichen mit den Ergebnissen, die man mittels Variablentrennung und einfacher Diffusionstheorie (P1 Approximation) erhält.
References
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© 2010, Carl Hanser Verlag, München
Articles in the same Issue
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- Summaries/Kurzfassungen
- Technical Contributions/Fachbeiträge
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- 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
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- 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
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
