Optimal Shielding Design for Minimum Materials Cost or Mass

Author:  Robert D. Woolley

Abstract:  The mathematical underpinnings of cost optimal radiation shielding designs based on an extension of optimal control theory are presented, a heuristic algorithm to iteratively solve the resulting optimal design equations is suggested, and computational results for a simple test case are discussed.  A typical radiation shielding design problem can have infinitely many solutions, all satisfying the problem's specified set of radiation attenuation requirements. Each such design has its own total materials cost. For a design to be optimal, no admissible change in its deployment of shielding materials can result in a lower cost. This applies in particular to very small changes, which can be restated using the calculus of variations as the Euler-Lagrange equations. The associated Hamiltonian function and application of Pontryagin's theorem lead to conditions for a shield to be optimal.
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Submitted to:  Nuclear Technology
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Download PPPL-5200 (pdf 2.1 MB 48 pp)
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