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DOE OSTI · 1878079

Equivalent Fundamental-Mode Source Simulations for Spherical Uranium and Plutonium Systems

Hutchinson, J.·Clark, A. R.·Kleedtke, N. A.·Rising, M. E.·Sanchez, R. G.·Weldon, R. A.
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Abstract

It is important in neutron noise measurements and reactor startup to understand how the source distribution in a system compares to the equivalent fundamental-mode (EFM) source. Deviation from the fundamental mode source distribution increases as the system $\kappa$ eff increases. A correction factor, g *, is a measure of this deviation, and is the focus of this work. Two methods were utilized to simulate g *. These methods are compared to each other and (where applicable) previous results. The effects associated with nuclear material inner radius, materials of reflectors, and reflector thickness are also investigated.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS97 MATHEMATICS AND COMPUTINGcriticality simulationsfundamental-modeintegral experimentsneutron noiseNuclear Criticality Safety Program (NCSP)subcritical multiplication

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Hutchinson, J., Clark, A. R., Kleedtke, N. A., Rising, M. E., Sanchez, R. G., Weldon, R. A.. 2022-06-15. Equivalent Fundamental-Mode Source Simulations for Spherical Uranium and Plutonium Systems. https://www.osti.gov/biblio/1878079

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