Test Design, Precharacterization,and Fuel Assembly Fabrication for Instrumented Fuel Assemblies IFA-431and IFA-432,

摘要

The thermal stored energy in a fuel rod is the driving function for the severest postulated nuclear energy-related accident,the loss-of-coolant-accident (LOCA). Because of this,the final acceptance criteria for emergency core cooling systems requires calculation of the stored energy and gap conductance of a fuel rod,both for normal operation and for the duration of the LOCA. Due to the lack of well-characterized data,some computer-coded mathematical models that have been developed to simulate fuel rod behavior over a wide range of postulated conditions are inadequate. These factors together contribute substantially to the stored energy uncertainty. This report is a resource document for future analytical and experimental work conducted for the Experimental Verification of Steady State Fuel Codes program as well as other reactor safety research and related industry safety programs. The test rationale,design,fabrication,and pre-irradiation characterization data are included in extensive detail to ensure that all pertinent information on the fuel assemblies will be available for future mathematical modeling and data reduction. The information is necessary to quantify the uncertainty in thermal stored energy and thus reduce restrictions on commercial power plant operation.