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DOE OSTI · 1402629

Adjoint-based constant-mass partial derivatives

Favorite, Jeffrey A.
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Abstract

In transport theory, adjoint-based partial derivatives with respect to mass density are constant-volume derivatives. Likewise, adjoint-based partial derivatives with respect to surface locations (i.e., internal interface locations and the outer system boundary) are constant-density derivatives. This study derives the constant-mass partial derivative of a response with respect to an internal interface location or the outer system boundary and the constant-mass partial derivative of a response with respect to the mass density of a region. Numerical results are given for a multiregion two-dimensional (r-z) cylinder for three very different responses: the uncollided gamma-ray flux at an external detector point, k eff of the system, and the total neutron leakage. Finally, results from the derived formulas compare extremely well with direct perturbation calculations.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSpartial derivativeperturbation theorysurface perturbation theory

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Favorite, Jeffrey A.. 2017-09-01. Adjoint-based constant-mass partial derivatives. https://doi.org/10.1016/j.anucene.2017.08.015

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