Progress with OnTheFly Neutron Doppler Broadening in MCNP
Abstract
The University of Michigan, ANL, and LANL have been collaborating on a USDOENE University Programs project 'Implementation of OntheFly Doppler Broadening in MCNP5 for Multiphysics Simulation of Nuclear Reactors.' This talk describes the project and provides results from the initial implementation of OnTheFly Doppler broadening (OTF) in MCNP and testing. The OTF methodology involves high precision fitting of Doppler broadened crosssections over a wide temperature range (the target for reactor calculations is 2503200K). The temperature dependent fits are then used within MCNP during the neutron transport, for OTF broadening based on cell temperatures. It is straightforward to extend this capability to cover any temperature range of interest, allowing the Monte Carlo simulation to account for a continuous distribution of temperature ranges throughout the problem geometry.
 Authors:
 Los Alamos National Laboratory
 Argonne National Laboratory
 University of Michigan
 Publication Date:
 Research Org.:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org.:
 DOE/LANL
 OSTI Identifier:
 1044100
 Report Number(s):
 LAUR1222277
TRN: US1203330
 DOE Contract Number:
 AC5206NA25396
 Resource Type:
 Conference
 Resource Relation:
 Conference: 2012 ANS Summer Meeting ; 20120624  20120628 ; Chicago, Illinois, United States
 Country of Publication:
 United States
 Language:
 English
 Subject:
 22 GENERAL STUDIES OF NUCLEAR REACTORS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 97 MATHEMATICAL METHODS AND COMPUTING; ACCURACY; ANL; CROSS SECTIONS; DISTRIBUTION; DOPPLER BROADENING; GEOMETRY; IMPLEMENTATION; LANL; NEUTRON TRANSPORT; NEUTRONS; SIMULATION; TARGETS; TESTING
Citation Formats
Brown, Forrest B., Martin, William R., Yesilyurt, Gokhan, and Wilderman, Scott. Progress with OnTheFly Neutron Doppler Broadening in MCNP. United States: N. p., 2012.
Web.
Brown, Forrest B., Martin, William R., Yesilyurt, Gokhan, & Wilderman, Scott. Progress with OnTheFly Neutron Doppler Broadening in MCNP. United States.
Brown, Forrest B., Martin, William R., Yesilyurt, Gokhan, and Wilderman, Scott. Mon .
"Progress with OnTheFly Neutron Doppler Broadening in MCNP". United States.
doi:. https://www.osti.gov/servlets/purl/1044100.
@article{osti_1044100,
title = {Progress with OnTheFly Neutron Doppler Broadening in MCNP},
author = {Brown, Forrest B. and Martin, William R. and Yesilyurt, Gokhan and Wilderman, Scott},
abstractNote = {The University of Michigan, ANL, and LANL have been collaborating on a USDOENE University Programs project 'Implementation of OntheFly Doppler Broadening in MCNP5 for Multiphysics Simulation of Nuclear Reactors.' This talk describes the project and provides results from the initial implementation of OnTheFly Doppler broadening (OTF) in MCNP and testing. The OTF methodology involves high precision fitting of Doppler broadened crosssections over a wide temperature range (the target for reactor calculations is 2503200K). The temperature dependent fits are then used within MCNP during the neutron transport, for OTF broadening based on cell temperatures. It is straightforward to extend this capability to cover any temperature range of interest, allowing the Monte Carlo simulation to account for a continuous distribution of temperature ranges throughout the problem geometry.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jun 18 00:00:00 EDT 2012},
month = {Mon Jun 18 00:00:00 EDT 2012}
}

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