Fuel management nodal model validation for the Maine Yankee Atomic Power Station

A physics nodal model employing the CASMO and SIMULATE codes has been validated for future cycle predictions of a full range of core physics parameters. Comparisons to both plant-measured and reload licensing calculated parameters for Maine Yankee Cycles 6 through 9 provide confidence in the predictive capabilities of the model. These cycles comprised changes in reload enrichment, a reconfigured control rod pattern and a transition from traditional OUT-IN to low-fluence and low-leakage core loading patterns. Despite these design obstacles, the model has provided sufficient physics parameter accuracy to establish core loading patterns and identify physics parameter changes which could impact core reload licensing