Possible Use of Measurements to Ament Cross Section Tables (PUMA)

Abstract

In a companion paper, the RAM flux mapping procedure has been demonstrated. RAM combines theory and in-core detector flux measurements, thereby recognizing a difference between the two. Assuming that the RAM "smoothed-out" flux distribution is exact, then the discrepancy with purely theoretical fluxes is due to inadequacies in the diffusion theory, homogenised core parameters. PUMA has been devised with the purpose of inferring adjustments in the homogenised core parameters from the theory vs. experiment flux discrepancy. This has been achieved by introducing influence functions similar to those defined by Buckler. A thorough mathematical analysis shows that influence functions are not all linearly independent and that it is crucial to use the criticality equation in the equation set. Numerical examples are shown to demonstrate the procedure.