Neutron reflection and leakage models for one-dimensional reactor computations
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M. P. de Abreu
Abstract
Exact discrete ordinates interface conditions were derived for neutron reflection and leakage for one-dimensional nuclear reactor computations with anisotropic scattering. The key to our derivation is a suitable reformulation of exact discretized equations – spectral nodal equations defined in the nonactive surrounding regions of nuclear reactor cores. As a result, interface conditions are obtained that can advantageously replace the nonactive surrounding regions of a nuclear reactor core in reactor computations. Numerical experiments with a representative one-dimensional code and an axial core model with anisotropic scattering were performed in order to illustrate the improvements that can be experienced by most one-dimensional discrete ordinates nuclear reactor codes with our interface conditions.
Kurzfassung
Es wurden genaue Schnittstellenbedingungen nach der Diskreten-Ordinaten-Methode hergeleitet für Berechnungen von Neutronenreflexion und Neutronenverlust bei anisotroper Streuung. Der Schlüssel zu dieser Ableitung ist eine geeignete Neuformulierung von genau diskriminierten Gleichungen – nodale Gleichungen, die in der nichtaktiven Umgebung des Reaktorkerns definiert werden. Es ergeben sich Schnittstellenbedingungen die die nichtaktiven Gebiete eines Reaktorkerns bei Berechnungen ersetzten. Es wurden numerische Experimente mit einem repräsentativen eindimensionalen Rechencode und einem axialen Kernmodell mit anisotroper Streuung durchgeführt, um die Verbesserungen zu zeigen, die mit diesen Schnittstellenbedingungen bei den meisten der eindimensionalen Reaktorcode nach der Diskrete-Ordinaten-Methode erreicht werden können.
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© 2005, Carl Hanser Verlag, München
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
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
