Eigenvalue Contributon Estimator for Sensitivity Calculations with TSUNAMI3D
Abstract
Since the release of the Tools for Sensitivity and Uncertainty Analysis Methodology Implementation (TSUNAMI) codes in SCALE [1], the use of sensitivity and uncertainty analysis techniques for criticality safety applications has greatly increased within the user community. In general, sensitivity and uncertainty analysis is transitioning from a technique used only by specialists to a practical tool in routine use. With the desire to use the tool more routinely comes the need to improve the solution methodology to reduce the input and computational burden on the user. This paper reviews the current solution methodology of the Monte Carlo eigenvalue sensitivity analysis sequence TSUNAMI3D, describes an alternative approach, and presents results from both methodologies.
 Authors:
 ORNL
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Sponsoring Org.:
 USDOE National Nuclear Security Administration (NNSA)
 OSTI Identifier:
 931544
 DOE Contract Number:
 AC0500OR22725
 Resource Type:
 Conference
 Resource Relation:
 Conference: 8th International Conference on Nuclear Criticality Safety, St. Petersburg, Russian Fed., 20070528, 20070601
 Country of Publication:
 United States
 Language:
 English
Citation Formats
Rearden, Bradley T, and Williams, Mark L. Eigenvalue Contributon Estimator for Sensitivity Calculations with TSUNAMI3D. United States: N. p., 2007.
Web.
Rearden, Bradley T, & Williams, Mark L. Eigenvalue Contributon Estimator for Sensitivity Calculations with TSUNAMI3D. United States.
Rearden, Bradley T, and Williams, Mark L. Mon .
"Eigenvalue Contributon Estimator for Sensitivity Calculations with TSUNAMI3D". United States.
doi:.
@article{osti_931544,
title = {Eigenvalue Contributon Estimator for Sensitivity Calculations with TSUNAMI3D},
author = {Rearden, Bradley T and Williams, Mark L},
abstractNote = {Since the release of the Tools for Sensitivity and Uncertainty Analysis Methodology Implementation (TSUNAMI) codes in SCALE [1], the use of sensitivity and uncertainty analysis techniques for criticality safety applications has greatly increased within the user community. In general, sensitivity and uncertainty analysis is transitioning from a technique used only by specialists to a practical tool in routine use. With the desire to use the tool more routinely comes the need to improve the solution methodology to reduce the input and computational burden on the user. This paper reviews the current solution methodology of the Monte Carlo eigenvalue sensitivity analysis sequence TSUNAMI3D, describes an alternative approach, and presents results from both methodologies.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

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Determining importance weighting functions for Contributon theory eigenvalue sensitivity coefficient methodologies
This study introduced two new approaches for calculating the F*(r) importance weighting function for Contributon and CLUTCH eigenvalue sensitivity coefficient calculations, and compared them in terms of accuracy and applicability. The necessary levels of F*(r) mesh refinement and mesh convergence for obtaining accurate eigenvalue sensitivity coefficients were determined for two preliminary problems through two parametric studies, and the results of these studies suggest that a sufficiently accurate F*(r) mesh for calculating eigenvalue sensitivity coefficients can be obtained for these problems with only a small increase in problem runtime. (authors) 
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