Startseite Technik Critical parameters and decay constants for one-speed neutrons in slabs and spheres with anisotropic scattering
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Critical parameters and decay constants for one-speed neutrons in slabs and spheres with anisotropic scattering

  • C. Yíldíz
Veröffentlicht/Copyright: 17. März 2022
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Abstract

Time-dependent, one-speed neutron transport equations with strong forward and backward scattering together with isotropic scattering are studied in homogeneous slabs and spheres. First, a simple formal equivalence between the transport equations for a critical and for a time-decaying system is established. Then, the transport equation is converted into a more conventional one. The FN method of solving the resulting transport equation is applied to the calculation of the critical parameters and decay constants for the fundamental mode of the flux distribution and one-speed neutrons in spheres and infinite slabs. Numerical results are given for a number of significant figures and compared with those already available in the literature.

Abstract

Untersucht werden zeitabhängige Transportgleichungen für Neutronen gleicher Geschwindigkeit mit starker Vorwärts- und Rückwärtsstreuung zusammen mit isotroper Streuung in homogenen Stäben und Kugeln. Ausgehend von der formalen Äquivalenz zwischen den Gleichungen für ein kritisches und ein zeitabhängiges System wird die Transportgleichung in eine eher konventionelle Form umgewandelt. Die Fn-Methode zur Lösung dieser resultierenden Transportgleichung wird angewendet für die Berechnung der kritischen Parameter und Zerfallskonstanten für Neutronen gleicher Geschwindigkeit in Kugeln und Stäben. Numerische Ergebnisse werden für eine Reihe signifikanter Fälle vorgestellt und mit Literaturdaten verglichen.

Acknowledgments

The author would like to express his gratitude to Professor Nils G. Sjöstrand, Department of Reactor Physics, Chalmers University of Technology, S-41296 Göteborg, Sweden, and Professor D. C. Sahni, Theoretical Physics Division, Bhabha Atomic Research Centre, Bombay 400085, India, for sending several matters relating to this manuscript. This research was partially supported by the Istanbul Technical University Re­search Foundation under grant ITURF-1372.

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Received: 2001-04-05
Published Online: 2022-03-17

© 2001 Carl Hanser Verlag, München

Heruntergeladen am 13.12.2025 von https://www.degruyterbrill.com/document/doi/10.1515/kern-2001-0107/pdf?lang=de
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