Shutdown Dose Rate Analysis Using the Multi-Step CADIS Method

Ibrahim, Ahmad M.; Peplow, Douglas E.; Peterson, Joshua L.; Grove, Robert E.

doi:10.13182/FST15-123

Title: Shutdown Dose Rate Analysis Using the Multi-Step CADIS Method

Abstract

The Multi-Step Consistent Adjoint Driven Importance Sampling (MS-CADIS) hybrid Monte Carlo (MC)/deterministic radiation transport method was proposed to speed up the shutdown dose rate (SDDR) neutron MC calculation using an importance function that represents the neutron importance to the final SDDR. This work applied the MS-CADIS method to the ITER SDDR benchmark problem. The MS-CADIS method was also used to calculate the SDDR uncertainty resulting from uncertainties in the MC neutron calculation and to determine the degree of undersampling in SDDR calculations because of the limited ability of the MC method to tally detailed spatial and energy distributions. The analysis that used the ITER benchmark problem compared the efficiency of the MS-CADIS method to the traditional approach of using global MC variance reduction techniques for speeding up SDDR neutron MC calculation. Compared to the standard Forward-Weighted-CADIS (FW-CADIS) method, the MS-CADIS method increased the efficiency of the SDDR neutron MC calculation by 69%. The MS-CADIS method also increased the fraction of nonzero scoring mesh tally elements in the space-energy regions of high importance to the final SDDR.

Authors:

Ibrahim, Ahmad M. ^[1]; Peplow, Douglas E. ^[1]; Peterson, Joshua L. ^[1]; Grove, Robert E. ^[1]

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Publication Date:: Thu Jan 01 00:00:00 EST 2015

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1214480

Grant/Contract Number:: AC05-00OR22725

Resource Type:: Accepted Manuscript

Journal Name:: Fusion Science and Technology

Additional Journal Information:: Journal Volume: 68; Journal Issue: 3; Journal ID: ISSN 1536-1055

Publisher:: American Nuclear Society

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats


                    Ibrahim, Ahmad M., Peplow, Douglas E., Peterson, Joshua L., and Grove, Robert E. Shutdown Dose Rate Analysis Using the Multi-Step CADIS Method.  United States: N. p., 2015. 
Web.  doi:10.13182/FST15-123.

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                    Ibrahim, Ahmad M., Peplow, Douglas E., Peterson, Joshua L., & Grove, Robert E. Shutdown Dose Rate Analysis Using the Multi-Step CADIS Method.  United States.  https://doi.org/10.13182/FST15-123

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                    Ibrahim, Ahmad M., Peplow, Douglas E., Peterson, Joshua L., and Grove, Robert E. Thu .  
"Shutdown Dose Rate Analysis Using the Multi-Step CADIS Method".  United States.  https://doi.org/10.13182/FST15-123.  https://www.osti.gov/servlets/purl/1214480.

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@article{osti_1214480,

  title        = {Shutdown Dose Rate Analysis Using the Multi-Step CADIS Method},

  author       = {Ibrahim, Ahmad M. and Peplow, Douglas E. and Peterson, Joshua L. and Grove, Robert E.},

  abstractNote = {The Multi-Step Consistent Adjoint Driven Importance Sampling (MS-CADIS) hybrid Monte Carlo (MC)/deterministic radiation transport method was proposed to speed up the shutdown dose rate (SDDR) neutron MC calculation using an importance function that represents the neutron importance to the final SDDR. This work applied the MS-CADIS method to the ITER SDDR benchmark problem. The MS-CADIS method was also used to calculate the SDDR uncertainty resulting from uncertainties in the MC neutron calculation and to determine the degree of undersampling in SDDR calculations because of the limited ability of the MC method to tally detailed spatial and energy distributions. The analysis that used the ITER benchmark problem compared the efficiency of the MS-CADIS method to the traditional approach of using global MC variance reduction techniques for speeding up SDDR neutron MC calculation. Compared to the standard Forward-Weighted-CADIS (FW-CADIS) method, the MS-CADIS method increased the efficiency of the SDDR neutron MC calculation by 69%. The MS-CADIS method also increased the fraction of nonzero scoring mesh tally elements in the space-energy regions of high importance to the final SDDR.},

  doi          = {10.13182/FST15-123},

  journal      = {Fusion Science and Technology},

  number       = 3,

  volume       = 68,

  place        = {United States},

  year         = {Thu Jan 01 00:00:00 EST 2015},

  month        = {Thu Jan 01 00:00:00 EST 2015}

}

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Works referenced in this record:

SCALE 6: Comprehensive Nuclear Safety Analysis Code System
journal, May 2011

Bowman, S. M.
Nuclear Technology, Vol. 174, Issue 2
DOI: 10.13182/NT10-163

FW-CADIS Method for Global and Regional Variance Reduction of Monte Carlo Radiation Transport Calculations
journal, January 2014

Wagner, John C.; Peplow, Douglas E.; Mosher, Scott W.
Nuclear Science and Engineering, Vol. 176, Issue 1
DOI: 10.13182/NSE12-33

Rigorous mcnp based shutdown dose rate calculations: computational scheme, verification calculations and application to ITER
journal, December 2002

Chen, Y.; Fischer, U.
Fusion Engineering and Design, Vol. 63-64
DOI: 10.1016/S0920-3796(02)00144-8

Novel hybrid Monte Carlo/deterministic technique for shutdown dose rate analyses of fusion energy systems
journal, October 2014

Ibrahim, Ahmad M.; Peplow, Douglas E.; Peterson, Joshua L.
Fusion Engineering and Design, Vol. 89, Issue 9-10
DOI: 10.1016/j.fusengdes.2014.03.014

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Similar Records

Title: Shutdown Dose Rate Analysis Using the Multi-Step CADIS Method

Abstract

Citation Formats

SCALE 6: Comprehensive Nuclear Safety Analysis Code System journal, May 2011

FW-CADIS Method for Global and Regional Variance Reduction of Monte Carlo Radiation Transport Calculations journal, January 2014

Rigorous mcnp based shutdown dose rate calculations: computational scheme, verification calculations and application to ITER journal, December 2002

Novel hybrid Monte Carlo/deterministic technique for shutdown dose rate analyses of fusion energy systems journal, October 2014

SCALE 6: Comprehensive Nuclear Safety Analysis Code System
journal, May 2011

FW-CADIS Method for Global and Regional Variance Reduction of Monte Carlo Radiation Transport Calculations
journal, January 2014

Rigorous mcnp based shutdown dose rate calculations: computational scheme, verification calculations and application to ITER
journal, December 2002

Novel hybrid Monte Carlo/deterministic technique for shutdown dose rate analyses of fusion energy systems
journal, October 2014