TIME DOMAIN REFLECTOMETRY LIQUID LEVEL DETECTION DATA EVALUATION AND CONCEPT ASSESSMENT

THIS PROGRAM DEALS WITH THE EVALUATION OF LIQUID LEVEL DETECTION DATA OBTAINED DURING THE MT-4 EXPERIMENT, WHICH IS THE LAST TEST PERFORMED IN THE LOCA SIMULATION IN NRU REACTOR PROGRAM. THESE DATA OFFER THE POTENTIAL OR RELATINGTHE ONLY FULL-LENGTH IN REACTOR REFLOOD INFORMATION ON N NUCLEAR-POWERED PWR FUEL BUNDLES TO COLLAPSED LIQUID LEVEL AND TWO-PHASE COOLING OF DEFORMED AND RUPTURED FUEL BUNDLES.IN THE MT-4 TEST, A TIME DOMAIN REFLECTOMETRY (TDR) A MID LEVEL PROBE WAS USED TO MEASURE TRANSIENT LIQUID LEVEL DURING THE REFLOOD PHASE. A VIDEO TAPE WAS MADE DURING THE COURSE OF THE TEST RECORDING THE CRT WAVE FORMS FROM THE TDRAND ARE THE ONLY COMPLETE DATA AVAILABLE FOR THIS INSTRUMENTFOR IN-REACTOR LOCA REFLOOD CONDITIONS. THE WORK IN THIS PROPOSAL WILL EVALUATE THE RELATIONSHIP BETWEEN THE TDR WAVEFORMS AND DATA FROM SELF-POWERED NEUTRON DETECTORS (SPND'S) AND THERMOCOUPLE DATA USING FOURIER TRANSFORMATION TE TECHNIQUES. THE RESULTS OF THIS WORK WILL DETERMINE THE FEASIBILITY OF USING THE TDR LIQUID LEVEL MEASUREMENT CONCEPT FOR IN-REACTOR APPLICATION. IN ADDITION, AN ANALYTICAL RELATIONSHIP WILL BE DEVELOPED FOR EVALUATING THECOLLAPSED LIQUID LEVEL AND COOLABILITY PARAMETERS THAT CAN BE EXTRAPOLATED TO CONDITIONS WHERE ONLY SPND AND TH THERMOCOUPLE DATA ARE AVAILABLE.