Critical Experimental Study of Integral Physics Parameters in Simulated LMFBR Meltdown Cores

摘要

A program of measurements designed to provide experimental data for the validation of analytical methods used in the neutronics part of LMFBR accident analyses has recently been completed at Argonne National Laboratory. A considerable volume of critical experimental data already exists for normal, undamaged LMFBR cores, and the size of the calculational and cross-section data errors is well established. However, this knowledge cannot be easily extrapolated to severely distorted accident configurations because of the large changes in neutron spectrum and system leakage properties (including streaming in large cavities) which are induced by redistribution of materials. The available experimental data on the physics of damaged LMFBR cores are inadequate for use in the systematic validation of calculational methods for a variety of reasons. The present program provides a clean, benchmark set of experiments with large reactivity changes (involving approximately 18.5% core volume distortions) for use in the methods validation. The reference configuration for the measurements consisted of a single core zone with a typical LMFBR composition. A sequence of idealized configurations was designed to follow from this reference to simulate, in a static or ''snap-shot'' sense, the sequence of configurations that might result from a loss-of-flow transient. (ERA citation 04:019183)