The Design of Reload Cores Using Optimal Control Theory

摘要: A formal approach for the optimization of final design reload cores has been devised and verified. The method is based on applying calculus variations (Pontryagin's principle) to normal flux depletion system equations. resulting set coupled system, Euler-Lagrange (E-L), optimality equations are solved iteratively. This done by assuming a loading pattern old fuel, first solving equations, then E-L modified using (or Pontryagin) condition, process repeated until no further improvements can be made. computer program, OPMUV, implementing these procedures written code handle two-dimensional, quarter-core symmetric configurations with up 241 assemblies 4 nodes per assembly one-group theory. It also capability optimizing over entire cycle as well just at beginning (BOC). results show that procedure does work. In all cases tried, led reduction in nodal peaks 1 3% designer-obtained within couple iterations. These savings carry comparable reductions pin peaksmore » when optimized patterns used four-group, fine-mesh calculations. Since changes each iteration limited ensure convergence, thus suited fine tuning normally obtained gain an extra few percent power flattening.« less